Uh oh!
So, you just bought your new fish and are only just now learning about this cycling thing…
Or, maybe you are following the terrible advice of the pet store employee who said you only need to run your filter for 24 hours before adding your fish.
Maybe it’s even worse. You killed all the good bacteria in your tank and have to cycle your aquarium all over again.
Don’t worry! These scenarios are much more common than you think.
If you can’t return your fish, then you have only one option:
You have to cycle your aquarium the old-fashioned way – with fish in the tank.
Today, I am going to show you how to successfully cycle your aquarium with fish inside.
If you haven’t bought your fish just yet, I recommend using the fishless cycle, which is an easier, faster and safer way to cycle your aquarium. Interested? FishLab’s fishless cycling guide will walk you through the process.
Contents
- What is fish-in cycling?
- Why shouldn’t you use a fish-in cycle?
- The secret to successfully cycling with fish in your tank
- Essential products to perform a fish-in cycle
- How do you perform a successful fish-in cycle?
- What’s next? Life after cycling
What is fish-in cycling?
The purpose of a fish-in cycle is to kick-start the nitrogen cycle, an invisible three-stage process where beneficial (good) bacteria establish themselves in your filter, keeping your fish safe from ammonia.
I cover the nitrogen cycle in much greater detail here. If you are new to the hobby, it’s worth reading because an effective nitrogen cycle is perhaps one of the most important parts of a healthy tank.
For the rest of you, here’s a quick recap of the nitrogen cycle in action…
Stage 1 Waste such as pee, poop and uneaten fish food break down, releasing ammonia, a toxic chemical, into the water.
Stage 2 Beneficial bacteria eat the ammonia and release nitrites, yet another toxic chemical.
Stage 3 A second type of beneficial bacteria eat the nitrites and convert them to nitrates, which are harmless in small amounts and are removed from your aquarium each time you perform a water change.
Just one problem…
There aren’t any beneficial bacteria in a brand new aquarium. And without it, toxic ammonia and nitrites build up, causing serious harm to your fish…
So, it’s up to you to kick-start the nitrogen cycle. And to do that, you need some help from your fish, well from their pee and poop.
As the poop breaks down, it releases ammonia and encourages the beneficial bacteria to appear.
You might have noticed a flaw in this…
If ammonia is harmful to fish, and you are using your fish as a source of ammonia, doesn’t this harm them?
Well, that’s exactly what brings me to my next point…
Why shouldn’t you use a fish-in cycle?
In an emergency, a fish-in cycle might be your only option. If that’s the case, cycling with fish is perfectly acceptable because your fish might die if you don’t.
But if you have a choice, then you shouldn’t be cycling your aquarium with fish inside.
Why?
Well, a picture says it best…
Yep, fish-in cycling is very stressful for your fish. And, many fish won’t survive the process. Those that do are often more susceptible to disease and live shorter lives.
I assume you want to keep your pet fish alive as long as possible, right? Well, a fish-in cycle is a terrible way to start.
So, why is a fish-in cycle so harmful to fish?
Well, during the cycling process you are waiting for beneficial bacteria to establish a colony in your aquarium. And once they do, they will be able to eat ammonia and nitrites as quickly as they are produced.
Just one problem…
While you are waiting for the bacteria to grow in numbers, your fish are going to be exposed to elevated levels of ammonia and nitrites. Even at low levels, these toxic substances can stress and severely irritate your fish.
Not only that, but a fish-in cycle requires delicate planning and leaves little room for error. It’s not exactly beginner-friendly.
Now… I’m not trying to say that fish-in cycling doesn’t work. It certainly can. But considering the obvious harm that it can cause your fish, it should only be done in an emergency.
To be honest, given that you can now cycle your aquarium without fish, it’s puzzling to see the dated fish-in cycle still being recommended.
So, why do people continue to give the advice that it’s okay to cycle your aquarium with fish in it?
I was chatting with my local, big-box pet store the other day, and the employee was preaching the wonders of fish-in cycling. I would also like to point out that he was trying to convince me to buy fish to go with my new aquarium.
The reason was pretty clear… An extra sale. A pretty scummy move, right?
But in other cases, the advice to cycle with fish is much less sinister.
You see, fish-in cycling is how your grandparents would have cycled their tank. Yep, this method has been in use for that long. In fact, this was the only way to cycle a tank back then.
In these instances, the advice to go with a fish-in cycle came from the best of intentions, people passed on what they learned years ago. You can’t fault them for that. But you can fault them for not keeping up with the times! Fortunately, you now know better!
Look, I’m sure some of you are going to disagree with me on this. Maybe you have successfully used a fish-in cycle hundreds of times without harm. That’s cool too…
But for a beginner, a fishless cycle is by far the best way to go. And in this case, a fish-in cycle should only be used when absolutely necessary.
The secret to successfully cycling with fish in your tank
I’m going to let you in on a little secret…
You can tell whether your fish-in cycle is going to be a success or failure before you even begin.
Seriously.
And, it all comes down to the number of fish you have in your aquarium.
More fish = more poop and pee
Since this waste breaks down into ammonia, your ammonia levels are going to rise rapidly.
And the faster your ammonia levels rise, the more harm done to your fish.
So, what is the correct number of fish to use in a fish-in cycle?
Obviously, this aquarium is too small for the number of fish…
The larger your aquarium, the more fish you can include in a fish-in cycle.
Rule of thumb: One fish for every 10 gallons of water.
So, if your tank is 1 gallon, only 1 fish. If your tank is 58 gallons, 5 fish.
Don’t know your tank size? Use FishLab’s gallon calculator.
But what if you have more fish than should be in your tank?
Ideally, you want to do one of the following:
1. Give your fish away – Either return your fish, give them to a friend or contact your local fish club to see if anyone will take them.
2. Buy a larger tank – Buying a larger tank will increase the amount of fish you can cycle with.
But what if neither of these is an option?
Well, unfortunately it’s time for you to make a judgment call.
Do you try and cycle your aquarium with all your fish inside and risk killing them all?
Or, do you euthanize some, giving the rest a much greater chance of survival?
It’s a tough decision that only you can make.
Decided to euthanize? Please read FishLab’s guide to humanely killing fish. If you have to do it, please do it correctly.
Essential products to perform a fish-in cycle
In addition to your fish, tank and equipment like filters and heaters, you need two very important products to ensure that your tank is cycled correctly…
1. An aquarium test kit
The problem with the nitrogen cycle is that you can’t see it. The only way to monitor the cycling process is to test for it. And to do that, you need a good aquarium test kit.
I recommend buying a master test kit like the one pictured above because it includes all the test kits you need to cycle your aquarium at one low price.
To learn how a test kit works, check out FishLab’s aquarium test kit guide.
2. Water conditioner
Or more specifically, Seachem Prime. I consider it to be the best aquarium water conditioner available.
Get to know this product. During a fish-in cycle, it’s going to be your best friend.
Seachem Prime serves two purposes. The first is making your tap water safe…
You see, tap water contains chloramine and chlorine, two chemicals. Not only are these chemicals toxic to fish, but they also kill that beneficial bacteria. And without that, your tank won’t cycle.
Fear not! A dose of Seachem Prime to your tap water before adding it to your aquarium will dechlorinate your water, making it safe for the beneficial bacteria and the fish when you finally add them.
Seachem Prime also has the added benefit of neutralizing ammonia, nitrites and nitrates in your aquarium for 24 to 48 hours, making them harmless to your fish.
With these two products on hand, you are now ready to begin.
How do you perform a successful fish-in cycle?
Before I continue, I want to make one thing clear:
The lives of your fish are at stake!
It’s important that you carefully follow this guide. Read each step twice if you have to. Make sure you completely understand what you are doing before proceeding.
I cannot guarantee that your fish will survive the cycling process – some are more sensitive than others. But by following this guide, you give them the best possible chance.
When it comes to fish-in cycling, you have two choices – cycling with Seachem Prime or with water changes.
A) Fish-in cycling with Seachem Prime
If you are a beginner or are just looking for the easiest way to perform a fish-in cycle, then choose this option. This method uses daily dosing with Seachem Prime to render ammonia, nitrites and nitrates harmless to your fish.
The advantage is that you will perform fewer water changes.
Jump to these instructions for a Seachem Prime fish-in cycle.
B) Fish-in cycling with water changes
If you want to use fewer chemicals, you can perform a fish-in cycle just with water changes. This method uses the diluting effects of fresh water to keep ammonia, nitrites and nitrates at a low level.
Note: This method of fish-in cycling still requires a bottle of Seachem Prime or other water conditioner to dechlorinate your tap water. It’s also nice to have on hand in an emergency – in case something goes wrong.
Jump to these instructions for a water-change focused fish-in cycle.
Performing a fish-in cycle with Seachem Prime
Step 1: Set up your aquarium
It’s time to set up your aquarium. And, that includes all the equipment – heaters, filters, air pumps… Get it in there! Don’t forget to rinse it with fresh water first!
The beneficial bacteria need a surface to cling to, namely your substrate and filter media. So by setting everything up, you give your bacteria as many surfaces as possible to cling to.
Add water to the tank, and don’t forget to dechlorinate it with your water conditioner first.
Finally, you want to keep all electrical equipment, such as heaters, filters and bubblers, switched on throughout the entire cycling process. Not only will this keep your fish as comfortable as possible, but it will also make your tank cycle faster.
Want to cycle your tank as quickly as possible? Check out FishLab’s tips for speeding up the cycling process.
Step 2: Adding your fish
Before you add your fish, you want to acclimate them first. This will give them the best chance of survival.
You want to feed your fish throughout the cycling process… You don’t want them to starve!
When feeding your fish, however, it’s important that you don’t feed them too much. The more you feed them, the more they are going to poop. And the more they poop, the faster your ammonia levels are going to rise.
Also, remove any uneaten food from the tank, a good aquarium net will make this easy. Any uneaten food left behind will break down into ammonia, causing the levels to rise.
If a fish dies during the cycle, remove it from the aquarium ASAP. Its decaying body will also give off ammonia. Don’t panic if one of your fish dies. It doesn’t necessarily mean that all your fish will – this one might have been extra sensitive.
Step 3: Test, test, test, and test again
Now, use your ammonia test kit every 24 hours.
What you are looking for is any sign of ammonia. Trust me. It won’t be long before it appears.
Once your test kit returns positive for ammonia, it’s time to move to the next step.
Step 4: Dealing with ammonia
Once you detect ammonia, it’s time to start dosing with Seachem Prime. Follow the instructions on the bottle to determine what a single dose would be for your tank – the larger the aquarium, the more Prime you will need.
Fortunately, a little goes a long way, and many of you will find that a single bottle of Prime will get you through an entire cycle.
For this method, Seachem Prime is the most important ingredient. You see, a dose of Prime will bind ammonia, nitrite and nitrate for 24 to 48 hours, making them harmless to your fish.
Picture Seachem Prime locking up ammonia, nitrite and nitrate in a jail cell for up to 48 hours. While in the cell, these nasties cannot harm your fish. However, once their time is up, and they are released, they will once again attack your fish.
It is for this reason that you need to dose regularly with Seachem Prime, to keep these nasties locked up.
A single dose of Prime will treat up to 1 part per million (ppm) of ammonia. Prime can be dosed up to 5 times safely. So, 2 ppm of ammonia can be treated with two doses of Prime, 3 ppm can be treated with three doses, and so on.
Anything less than 1 ppm should be treated with a single dose. Between 1 ppm and 2 ppm, two doses. You get the idea. Oh, and it goes without saying that it’s better to overdose than underdose.
Keep dosing and using your aquarium test kit daily. At this stage, you need to perform a 50% water change.
Once your test kit reads 2 ppm of ammonia, you should perform a 50% water change. This should cut your ammonia levels roughly in half.
Repeat this process until you notice that your ammonia levels are not rising as quickly as before. Typically, this will take a week or two. When this happens, you are ready to move to the next step.
Step 5: Nitrites start to appear
Next, you need to test for nitrites. If none are present, keep repeating the previous step and testing for nitrites daily until you get a positive result.
Now that nitrite has entered the equation, you need to make sure you are dosing with enough Prime to protect your fish from both ammonia and nitrites.
Fortunately, working out your new dosage is pretty simple – just add your nitrite and ammonia readings together.
Let’s say your test returns the following…
| Ammonia | 0.25 ppm |
| Nitrite | 1.5 ppm |
Adding the two together will give you a total of 1.75 ppm. A double dose of Prime will take care of it.
This time, if your combined ppm of ammonia and nitrite reaches 4, perform a 50% water change.
Keep repeating this. You will eventually notice that your ammonia drops to zero. This is a good thing – bacteria are eating the ammonia as quickly as it is being produced, resulting in a zero reading.
Continue daily dosing and testing for ammonia and nitrites. Once your nitrite levels stop rising as quickly, you are ready for the next step.
Step 6: Nitrates appear
Now, you want to test for nitrates. If none are present, keep repeating the previous step and testing for nitrates daily until you get a positive result.
Once nitrates are present, you are nearing the end (woohoo!). Continue testing for ammonia, nitrites and nitrates. Your ammonia levels should still be zero, and your nitrite levels should be declining.
Keep dosing with Prime until both your nitrite and ammonia levels are zero. At this stage, the beneficial bacteria are eating them as quickly as they are being produced.
Congratulations! You have successfully completed a fish-in cycle.
Performing fish-in cycling with water changes
Step 1: Set up your aquarium
It’s time to set up your aquarium. And, that includes all the equipment – heaters, filters, air pumps… Get it in there! Don’t forget to rinse it with fresh water first!
The beneficial bacteria need a surface to cling to, namely your substrate and filter media. So by setting everything up, you give your bacteria as many surfaces as possible to cling to.
Add water to the tank, and don’t forget to dechlorinate it with your water conditioner first.
Finally, you want to keep all electrical equipment, such as heaters, filters and bubblers, switched on throughout the entire cycling process. Not only will this keep your fish as comfortable as possible, but it will also make your tank cycle faster.
Want to cycle your tank as quickly as possible? Check out FishLab’s tips for speeding up the cycling process.
Step 2: Add your fish
Before you add your fish, you want to acclimate them first. This will give them the best chance of survival.
You want to feed your fish throughout the cycling process… You don’t want them to starve!
When feeding your fish, however, it’s important that you don’t feed them too much. The more you feed them, the more they are going to poop. And the more they poop, the faster your ammonia levels are going to rise.
Also, remove any uneaten food from the tank. This, too, will break down into ammonia if left behind.
If a fish dies during the cycle, remove it from the aquarium ASAP. Its decaying body will also give off ammonia. Don’t panic if one of your fish dies. It doesn’t necessarily mean that all your fish will – this one might have just been extra sensitive.
Step 3: Test, test, test, and test again
Now, use your ammonia test kit every 24 hours.
What you are looking for is any sign of ammonia. Trust me. It won’t be long before it appears.
Once you notice ammonia building up, it’s time to test your aquarium twice a day. And, you need to make it a routine. If you leave the house during the day, morning and night are fine.
Step 4: Water change after water change
You want to keep the ammonia levels low, at a tolerable level for your fish. So, 0.25 parts per million (ppm) or less is your goal.
The moment you notice the ammonia levels reach 0.5 ppm, you want to perform a 50% water change. That is, remove 50% of the water from your aquarium and replace it with fresh water. Don’t forget to add the dechlorinator!
What this does is remove some of the ammonia from your aquarium, diluting it and lowering the levels.
Now, just how often you need to do this entirely depends on the size of your tank and how many fish you are cycling with.
Some of you might only need to do a water change twice a week, but others might need to do it twice a day. That’s fine. Let the test kit determine how often to do a water change.
Keep this up for at least a week before moving to the next step.
Step 5: The first beneficial bacteria appears
After a week, you will notice that your ammonia levels are not rising as quickly as they were before. This is a good sign that the first beneficial bacteria has entered your tank and is eating the ammonia, helping to keep the levels down.
To make sure that this is the case, you now want to test for nitrites. So, use your nitrite test kit. If it comes back positive for nitrites, congratulations!. You are in the first stage of the nitrogen cycle, but your work is far from finished…
Don’t worry if you don’t see nitrites yet. Simply repeat Step 4 and continue testing for nitrites until you do. Be patient. Remember… Fish-in cycling takes a lot longer than fishless cycling.
Step 6: More water changes
If anything, nitrites are more toxic than ammonia. You want to keep nitrites as close to zero as possible. And to do that, you must continue performing water changes.
Continue monitoring your ammonia and nitrites on a daily basis, and perform water changes when your nitrite levels rise.
Keep doing this for at least another week before moving to the next step.
Step 7: The second beneficial bacteria appear
After another week, the nitrite levels should not be rising as quickly as they were before. This is a good sign that the second beneficial bacteria is beginning to grow in your aquarium.
To make sure, grab your nitrate test kit. If it returns positive for nitrates, celebrate! You are on the home stretch.
Again, it can take longer than a week for nitrates to appear. Just keep repeating Step 5 until your nitrate test indicates that they are present in your tank. Patience, patience, patience. Did I mention patience?
Step 8: Continue testing and performing water changes
All that’s left to do is to keep testing, monitoring your ammonia, nitrite and nitrate levels.
If your nitrate levels creep over 40 ppm, it’s time for a water change. Although if you are performing water changes to keep your nitrites low, I’d be surprised if your nitrate levels ever reach this.
Continue this process until both the ammonia and nitrite levels read zero on the same day. Remember, the entire cycling process can take months. So again, be patient.
What’s next? Life after cycling
Woohoo!
You did it!
The beneficial bacteria in your tank are in high enough numbers that they can eat ammonia and nitrites as quickly as they are produced.
It might have taken a long time, but trust me, it was worth it!
Your tank is now safe for your fish. Any fish that survived deserve a medal of honor because they made the tank safe for any new fish you want to add.
On that note…
If you want to add more fish to your tank (assuming your tank is large enough), wait a week before adding a maximum of three. This gives the bacteria a chance to adapt to the increase in waste and grow in numbers to deal with it.
Still want to add more fish? Wait another week and repeat.
And remember, from this point on, nitrates will consistently build up in your aquarium. This is a major reason why we perform regular water changes – to keep the nitrate levels low.
Conclusion
Phew, you did it. I knew you could!
By cycling your aquarium, you give your fish the best possible chance to live a happy and healthy life.
Once the nitrogen cycle has started, it consistently runs in the background.
But you are not home free just yet…
You still need to regularly monitor your ammonia and nitrite levels to ensure that nothing goes wrong. I recommend that you include testing your tank as part of your regular water change routine.
Do you cycle your aquarium with fish inside? Let me know in the comments below!
I also use this site as an excuse to spend lots of money on testing and reviewing different aquarium products! You can find my reviews here.
So with all the testing and always getting the same results, I decided to get and try the green killing machine (as was recommended on Fishlore?). I got it Thurs. and as of Friday night could see improvement. This morning, it looks So much better! Can finally see details in the back of tank and I have not done a wc since Monday. Too busy and sick and things seemed ok or the same at the time. Also one more note, I was testing water am and pm – that was why the light was a challenge. 😉 sunlight vs. night lights. 🙂
All the best Ian!
Hi Jenna,
I’m glad that was an easy fix. But keep in mind that while the Green Killing Machine will fix the problem (the green/yellow free floating algae) it doesn’t fix the cause. Ideally, you wouldn’t want the free-floating algae to appear in the first place. Now you are testing correctly, are your water parameters as expected?
Yes, got it. Watching the feeding. Keeping up with water changes. I did check out AQ Advisor and noticed it recommended 26% wc every week and that my tank was 104% stocked?. :l So I will keep a close eye. Did manage another wc today and cleaned some more. Still a bit cloudy, but So much improved. 🙂 It’s the first time I have seen it get better without a wc. 🙂 And I skipped the bio on the wc. Just used the API Stress Coat+ water cond.
Parameters are as before every time the same or close? Ph 7.4, Ammonia – 0 or just a bit more but not .25 (which is the same as my tap water?), Nitrite – 0, and Nitrate – 0 or possibly a bit more but not fully 5ppm (given 5ppm is my base with tap water). Test looks darker than 5ppm but not as dark as 10 ppm.
That’s awesome to hear! I’m so happy for you. Sounds like you have gotten a good handle on it.
On the testing, if your nitrates are continually getting darker, then it’s possible your tank is actually cycled. I’d observe this over a week or two, without a water change, to make sure. You should see the nitrates visibly climb on your test over this period
Hi Ian,
So to follow-up on your advice to me on the Cloudy Water page…
“If I was in your position, I would perform a 100% water change and stop adding anything to the tank besides water conditioner. From here, attempt to carry out the cycle. If it’s a bacterial bloom from cycling, the cloudiness should come and go.
You would be at step 4 in the fishless cycle. Just keep monitoring that ammonia and keep it at around 0.25. From here, you should see nitrites within 3 weeks and from there it’s just more waiting.”
You stated I would be ** at step 4 in the fishless cycle** ? But I Have Fish in my tank? 4 Glow tetras 4 Penquin 1 African Dwarf frog and 1 Nerite snail? So you mean fish-in? cycle? Or am I not understanding something?
Also, I had 2 other thoughts.
I have been planning on getting an aquarium for my son after this was all settled. Maybe I get it early, set it-up and put them there until her tank is fixed?
OR
I mentioned I had a filter issue at one point and used another filter. I have a 30 gallon aquarium I have never used. I bought it used from a couple who had goldfish but needed baby space.
I have the filter – I did use it 2x when while doing a wc my filter stopped working for a bit (forgot to unplug it before the water got lower). It has been sitting unused in a bucket still with the same carbon/sponge/bio? They were unopened until end of Sept. when I got my tank and found out it had no filter in the kit. I put the filter together and put it to use to get our tank started, until I got the filter that was supposed to come in the kit.
I thought I potentially could start-up that aquarium (vs. buying all new in such a short time – hard to do when busy with school and activities all week)? The thing is it is 30 gallons vs.16 gallons. Could I fill it half-way? I don’t have any rock or anything to put in it. There is some sort of white plastic base I could leave in? Not sure what it was for? Then I guess I could hopefully quickly prep it and keep them there until I get their tank back in order? Maybe that is best?
Either way I now have a bottle of Seechem Prime. I also bought some Aquarium glue just in case? I have never used a used tank? She said she put Vaseline in the seams to keep it ok? That was easily 7 years ago when I first got it from her. And hopefully just a rinse with hot water will be ok with this option? Sorry. Lots of ?’s here I know. The 30 gallon tank is 2 floors down. Not so convenient, but maybe best option if you think worth it? Only thing is in the mean time, what do I do about fish in the 16 g tank as is. Just keep changing water weekly or so? And keep an eye on Ammonia etc.?
EXTRA note: This evening the tank looks Even More Cloudy. 🙁 Goodness wonder if they are having trouble seeing the food? The tests came back: Ammonia .25? Nitrites 0 and Nitrates 5 or I guess 0 given my Nitrate-y tap water?
Sorry, completely my mistake. My old brain often gets mixed up when replying to so many different comments. You are correct, I meant fish-in cycle. Step 4.
Regardless of which option you choose, you still need to cycle both fish tanks. Whether you do fish-in or fishless, it won’t make too much difference, thousands of people have seen success with either.
If your tank is 7 years old, depending on how it’s been stored, it’s possible it needs a re-seal. This would involve cutting away the existing silicone and reapplying new. It’s quite a project. Aquarium glue won’t cut it. I’d seek expert advice on whether this is the case, as there is nothing worse than dealing with a water leak with a fully stocked aquarium. I’ve had a couple in my time keeping fish and it’s a stressful disaster.
Also, I wouldn’t expect to see any movement yet. Cycling is slow. I’d do what I said in the previous comment and discontinue additives. Follow the cycle instructions and react according to the test kit. Unfortunately, cycles differ and there are no “exact” instructions. Your test kit will give you all the clues on how to proceed.
Hi Ian,
So, I am not liking the idea of redoing the old aquarium. But I was thinking, as I would need to cycle the water in the 30 gallon anyway, maybe I get started on that and if I notice a leak as I am filling it or what, it won’t matter as my fish will be in the 16g waiting for a cycled 30g? Curious what the time-frame on that might be and can I just fill it up half-way for this purpose? It is like 18 high I think? 30 long?
In the meantime, my 16g was last changed I think on Wed. or Thurs.? Forgot to mark it down. Normally I would do at least a 10% water change. Again on Wed. or Thurs.? I am also due for a carbon change on 2/20.
Can I stick with this? Do you think there is any chance my tank IS cycled? I have tested since Fri night and keep getting Ammonia at .25 or maybe I AM reading it wrong and it is 0? Nitrate at 0, Nitrate at 0 (adjusted for my 5 ppm tap water)? Maybe I am reading that a little off too? Maybe it is slightly more than 5ppm?
I am SO nervous about a 100% water change as you mentioned. Will that shock my fish? Wipe out Any good bacteria I might have? That is why I am wondering about any chance it is cycled or trying to go with setting up the old tank as a temporary plan B?
We have somehow struggled along this far, I don’t want to kill anything off if I can help it. 🙁 Same readings came back today as last night/morning etc. since Friday. And cloudiness is still high like yesterday, but not worse yet. It does still have this weird yellow/green color. It doesn’t show in the vials prior to testing, but it is visible in a 16 oz. cup if I place it in front of something white.
Hi Jenna,
Again, it’s best if you change as per your test kit. Let that determine how often you change. Saying “just change this often” will cause even more problems.
If you are not confident doing a 100% water change, perform two or three 50% ones over the next three days. If you do a 100% water change, you want the parameters (ph, temp, etc to match) otherwise it will stress out your fish. Since you are a beginner, and it doesn’t appear you are confident, I’d probably stick with the 50%. A 100% waterchange is best done in an emergency. However, I’d classify this as an emergency.
A water change won’t affect your bacteria. Unless you forget to condition the water.
Also, I’d say that the next effort of cycling STARTS once the water is changed. Again, why I said to start here is it’s possible one of the many additives that have been dosed in the tank is responsible for hampering it.
If your ammonia is 2.5 and nitrates are not raising, your tank isn’t cycled.
I’d advise joining a Online Aquarium Forum if you want a community to talk to and gather feedback off. You’ll receive plenty of support here.
Ok. Thanks Ian. I did another 50% water last night (following the one last wed/thur?). Still not a lot of cloudy movement. I added NO chemicals other than a water conditioner. Morning readings same as ever. Ammonia looks .25 or lighter. Nitrite 0. Nitrate 5ppm or 0 given tap water. Just out of curiosity, I tested the Ammonia in my tap water. It looks the same the tank. 0-.25? Does that tell anything? Also, I feel like am readings always seem to look more like 5ppm for Nitrate and then at night they look a bit darker but maybe that is just the lighting? I did check out a forum online too thank you!
I just trust your judgement more. 😉
Hi Jenna,
I’d do a second water change, as we discussed earlier, we want to get rid of that yellowy stain almost completely, so we can see if it comes back. This way we’ll know id something inside your tank is responsible.
When viewing your test results, it should always be done in natural daylight, the color of your indoor lighting can seriously throw the results out. If you take the tests outside, you can be more confident in your results.
So, do another water change, then re-test your aquarium for:
pH
Ammonia
Nitrite
Nitrate
Water temperature
And record these. That’s all we can do for now. After you record those, and you are confident you are testing in natural day light, we can proceed.
And forums are great, there are plenty of people just as knowledgeable as me there – plenty of people take this hobby really seriously! It’s a good thing for beginners looking for advice 🙂
Thank you so much for this page. I’m among those who was told by a big pet store that I only had to wait 48 hours to add fish, so I’m now trying to run a fish-in cycle with 6 fish (3 guppies, 3 guaramos) in a 20g tank that I started 9 days ago – it showed its first ammonia (0.5) today and I treated with Prime. However – I also have a smaller, 5g tank that was newly set up, doesn’t have fish yet, and hasn’t started its cycle yet – it’s only been running for 2 days. Would my fish have a better chance of survival if I moved 3 of them to the 5g tank (guppies, I guess, because they’re tiny)? I somehow want to help all of them survive.
The pet store sold me a bottle of TopFin “quick start” bacteria – that’s why he said it was safe to add in fish right away – does that actually work?
Hi Allyson,
Classic Petsmart. No, adding topfin “quickstart” doesn’t automatically cycle your tank. The purpose of bottled bacteria is to speed up the cycle. It doesn’t instantly cycle or make a tank safe for fish. Going further, there are different strains of bacteria. The strain found in API quickstart or DR Tim’s one and only (it’s the same stuff, different label) are the same as the bacteria that form in a cycle. There is much debate as to whether other brands actually help speed up a cycle at all, but I won’t go into that.
As for the fish, I assume you mean gourami? Depending on the species, you may find that these fish are either best kept on their own or in male-female pairs. They are a mixed basket and there is no guarantee they won’t bully other fish in your tank.
A 5 gallon is too small for 3 guppies. I feel they will have a better chance of survival in the 20g. 5 gallon tanks are not good for much other than shrimp/snail tanks or a lone betta.
Thanks so much for this. Yes, the 5 gallon tank was originally purchased for a single Betta, and just hasn’t been used for several years. I’ll keep them all in the 20g and watch chemical levels carefully. Thanks for the informative webpage.
And yes, gourami. So far, all of the fish have gotten along without any trouble. Once the tank has cycled, can we add a few more fish to it? If so, are there ones you would particularly recommend? The store said 1 fish inch per gallon of water, but now I’m wondering if that was accurate given the other questionable advice we got.
Unfortunately, the “1 inch per rule” isn’t a good one to follow. For instance, an 2 inches of a Koi would be best suited for a tank around 60 gallon. Even your 3 guppies would be too much for the 5 gallon. Fish tanks always hold less than you think. I would be hesitant to add any more fish to your 20 gallon. I would recommend finding a smaller “independent” fish store and going to them for advice, they will list all your options honestly, since they rely on your fish living for you to come back. The big chains seem to just want that one big sale.
It’s over an hour to anything but the big box pet supply stores, but I’ll approach everything with far more caution from now on and will do my own research.
My tap water PH is testing between 6-6.5, which I’m thinking may work in the fish’s favor during cycling. But I’ll stick with the fish I have, watch chemicals closely, and do plenty of water changes. Three days in and so far, everyone looks okay.
That sounds like a better idea. I know all this can take a lot to take in at the beginning, but trust me, it definitely gets easier.
Just be mindful that if the pH gets too low (closer to 6 or under) it can seriously slow down the cycling process. It will still happen, it just takes longer.
Hang in there, even a “fast cycle” can take some time. It’s all patience from here on out.
Hi Ian!
Brace yourself for another slightly weird question. I was wondering, couldn’t we fishless-cycle a separate tank while Betta is recuperating, then transfer him to it when he’s fine?
Also another weird question — is it a nasty/unwise/ridiculous idea to save Gup’s used filter sponge to “seed” Betta’s tank? Gup’s tank has a “traditional” filter, with layers of spongey (and stony) filter media within a plastic casing; sometimes one of the sponges deteriorates to the point where we have to replace it with a new one. We actually sit that old sponge with the new one for some days to seed it a bit, which led me to wonder if we could “share” it with Betta haha… Thoughts?
Hi Catherine,
Not weird at all. I would think that your fish-in cycle would have completed by the time your fishless cycle neared the end though. If you do go down this route, don’t forget to acclimatize him when you transfer him
If the filter has not been removed then it could contain some beneficial bacteria. How much will depend on how far along your cycle has progressed. If it’s fully loaded with the stuff, it could speed up the cycle of your new tank. Otherwise you may not find it noticeably makes a difference. I’d try either DR Tim’s one and only or Tetra Quickstart (both are the same strain of bacteria) in addition to this.
Thanks Ian!
Yes. the filter isn’t removed. Gup’s tank is cycled, so that’s why I thought their old sponge must have a fair bit of stuff. But is it “unhygienic” to share it with Betta?
On another note, what would account for an occasional re-appearance of ammonia in a cycled tank? About 0.25, which goes back down to 0 after a water change or two?
Unless your tank has a disease outbreak or similar, there isn’t anything wrong with sharing a filter. It’s how plenty of newbies kickstart their cycle.
Such a small amount of ammonia? I’d monitor what happens prior to it’s appearance. feeding time? three days before water change day? Etc. It’s possible your tank isn’t fully cycled in relation to the bioload yet. It’s honestly hard to say without backtracking what happened prior to measuring it.
Thanks so much Ian.
Yes, just a hint of it. And yes, it does sort of tie in to feeding time sometimes I think… how long a gap should there be between feeding and testing?
I think the tank is fully cycled though? as the weeks between such occasions are fine.
Try giving it an hour or two after feeding and see what the results are. It’s possible the proteins in the food are rapidly breaking down and causing a slight ammonia rise. This is just theory based on what you have stated. Admittedly, I have no experience with food releasing ammonia so quickly. You’ll need to do your own testing to confirm the food is in face responsible for these ammonia spikes.
Thanks so much Ian.
We’re thinking of switching Betta’s sponge filter to a slightly bigger one — what would be the best way to go about doing this? Of course his current filter has been around awhile and has a fair bit of good stuff on it; we were just thinking it might be a bit too small.. being a Betta I don’t think we can run BOTH filters at the same time..
Can you run both on the lowest setting? Or reduce the input somewhat, say with a sponge or something similar to slow down the flow?
Possibly, though it’s going to start being kind of cramped in there haha… Do you mean to run both together for a period of time, or forever?
Don’t worry, it’s only temporary. It generally takes 2-4 weeks for the filter to colonize.
But it has to be connected to a working pump, yes? As in, the filter needs to be functioning in order to colonize? Not just sit there?
This is correct, yes.
Thank you so much!!
Hi Ian,
Could any of these cause a re-appearance of ammonia in a cycled tank?
1) Gunky filter
2) Dirty gravel
3) Underwater walls and floor that have pretty much never been wiped because they don’t *look* dirty.
Forgot to add
4) Overfeeding (was trying new food)
1 and 2 could, but only if you weren’t performing regular maintenance on them.
3, not so much.
4. Certainly. Overfeeding is one of the most common causes of ammonia spikes.
Sigh. Well we cleaned the gravel and the filter anyway (gravel didn’t seem gunky at all; filter mildly). But I suspect it might be the overfeeding (enthusiastic kids)… Does this mean a “mini cycle” thing?? Please advise on how to treat, thanks so much.
The only way to really treat it is to administer the correct dose of Seachem Prime. The beneficial bacteria will do the rest. Because your tank is already cycled, you just want to limit the stress placed on the fish while your bacteria catches up to this “extra amount.” It should be done in a day or two. You can skip feeding for a day to help, many fish can last up to a week without feeding, this will ensure that no additional ammonia is added while your tank is catching up.
Thanks so much Ian.
So water changes as usual? Or extra water changes?
A water change won’t hurt. In fact, it’s only a good thing, especially if you have cleaned the tank to remove any additional food or poop. I usually give the advice of water conditioner first because it solves the problem immediately, as far as the fish are concerned. From here, you can monitor your tank and use the test kit to make the call on how to proceed.
Hi Ian. I am currently into a 2wk fish in cycle and I have 1 goldfish that was burned very badly by the ammonia. I do not have a quartine tank set up and he looks like he may have a secondary infection. I did order a filter from angel fish and expecting its arrival today however I am not sure what to do with this one poor fish. Can you help?
Hi Elizabeth,
If your fish is suffering, you’ll need to try continue the cycle while keeping the water as pristine as possible. Depending on what the secondary infection is, you may need a specific medication. To give your fish the best chance of survival, you’ll want to keep ammonia and nitrite as low as possible. This will likely require daily water changes. Check with your test kit and take action as needed. Unfortunately, there is no guarantee your fish will survive this, but it will give it the best chance.
Oh dear. We were given a Water Garden for Christmas and set it up according to the instructions. One Betta fish, 3 gallon tank. It never mentioned anything about the nitrogen cycle. The first fish died the next day. I cleaned everything and acclimated the next Betta. (Following better instructions than came with the kit) Do you happen to know if growing plants affects this cycle? I’m about to make this an experiment for my son. I’ve been googling all day, trying to figure out if the current is too strong, whether his fins should be fluttering all the time, you name it. Don’t really want to kill this one!
Hi Angelica,
Unfortunately, the aquarium cycle is a beginner trap – that is often missed. Don’t worry, you are not alone here.
Growing plants won’t have noticeable any impact on the speed that the tank cycles. Betta come from calm almost still water, if the water current is strong, it will stress your betta which will lead sickness or even death. I cannot sayt how much current your water garden creates.
I’m bookmarking your site; it’s been the most helpful in my frantic googling. The filter I’ve put all the way to the floor to avoid sucking up the fish and the output is already softened by a plastic sponge. The fish is floating just fine and slept on the gravel without tucking himself anywhere. I’m going to see if there is a sponge that would fit over it when I go to the pet store today to pick up a test kit and hopefully some prime and a siphon. I no longer trust the kit. I honestly think we may have picked a sick fish from the start. This one is much more active and inquisitive. He may have fin rot, but I’m hoping that maybe it’s just fins burned from ammonia? Is that a thing? This kit is now just a 3 gallon tank with a lid I happen to grow things on.
Hi Angelica,
Fin rot can be caused by many things, bad water parameters being one of them. cycling your tank and doing regular water changes/tank maintenance will go a long way in preventing this. Fortunately, fin rot is very reversible. And yes, it certainly is possible you picked up a sick fish from the start, if it was a betta, these can be kept in some really poor conditions prior to being purchased.
Hi Ian,
I have another slightly weird question today (and please feel free redirect me and post this to a more appropriate post if you have one) — we were wondering if gravel should always remain wet and in the tank, from the standpoint of the beneficial bacteria of course. That is, is it bad if the gravel is ever taken out of the tank to be washed for instance? How long does the bacteria survive out of the tank? Thank you!!
Hi Catherine,
Admittedly, this ones a bit more out of my expertise as people don’t really take gravel out of their tank with the goal of keeping the beneficial bacteria alive, not unless it’s being transported in which case it will be sitting in tank water anyway. If you are feeding correctly and regularly gravel vaccing, the gravel in your tank should hardly gunk up at all. A little gunk is okay – a fish tank is not a pristine environment. Your fish live in “gunky water.” It’s kinda their thing. I don’t think I have come across a fishkeeper who includes washing gravel as part of his weekly routine.
If you are exceptionally concerned, clean half at a time. By clean I mean take it out and swirl it in tank water, rubbing lightly at stubborn bits. Next week clean the remaining half.
And again, while some of the beneficial bacteria can be found in your substrate, most of it is in the filter. This is why adding gravel substrate to speed up a cycle is generally slower than adding a pre-cycled filter.
Thanks a million Ian!!
Hi Ian! I have a slightly weird question today, so please bear with me! You know how we’re doing the “daily water changes while cycling because of the Betta healing thing” right? Well, I’m wondering – in our case – when ammonia and nitrite are zero, does that mean the tank’s successfully cycled?
I mean, I know in “regular” tanks that means they’re cycled, but in our case, the water’s being changed every day – it’s about as pristine as it could get. At this point, ammonia’s finally down to zero and nitrite is a very light 0.25 (ammonia was at 0.25 for the longest time and nitrite 0.25 to 0.5).
So I’m wondering, when both are down to zero, is the tank truly cycled? Or do our daily water changes somehow give a…“false positive”? In our cycled tank for instance, we change the water weekly – we KNOW (and sometimes test, just to be sure) that ammonia and nitrites are always zero; only the nitrates go up some. But in this tank, when the ammonia and nitrites are zero, if we were to say, not change the water daily anymore, would the ammon and nitrite suddenly reappear? In which case, it would mean the tank *wasn’t* truly cycled right? And in which case how would we know when it was??
Sorry, I know it’s rather a weird, convoluted question! Hope you get what I mean ^o^’
For you, it’s a weird one. If you are keeping ammonia at 0.25 then that’s the amount of ammonia that your beneficial bacteria will be able to break down. So while your tank may technically be cycled, it may only be able to break down 0.25 of ammonia within a set period as the beneficial bacteria hasn’t grown in number to break down more – beneficial bacteria adapts to the amount produced, that’s why in a fishless cycle we aim for 4 ppm of ammonia.
So yes, your tank is cycled once these reach zero, but there is no guarantee it will be able to go a week without a water change, as a normal tank would. Once your fish is healed, and you slow down on the water changes, it’s possible you’ll see an ammonia or nitrite spike. If this is the case, just proceed with a fish-in cycle in the usual way.
Yes agree, thank you so much! I guess once he’s completely healed, we’ll slow down the water changes very gradually and monitor. Possibly theoretically the beneficial bacteria would also be very very slowly growing in the meantime and can deal with the eventual (gradual) slow down in the water changes? I remember when we were cycling the gup tank way back when, ammonia and nitrite never went beyond 0.5 either (hmph, looking at the test results online now, it looks like our ammonia was more like 0.5 than the 0.25 we always thought). At that time we just dealt with it with daily water changes and eventually it successfully cycled.
If you slow down the water changes then the beneficial bacteria will absolutely gradually grow in number to adapt to the increase in ammonia produced. It may be a balancing act though, lucky you have gotten good at your testing during this period! I’ll bet you’ll be glad when this ordeal is over!
Oh you bet!! Not that we ever regret adopting him — he’s so cute lol. I’m thinking once his fins have fully regenerated, we’ll still keep up the daily changes for some time, but decreasing the amount very gradually by say 5% every few days..or something like that. And then when we see that ammon and nitrites manage to consistently keep to zero, we’ll gradually increase the spaces between changes, say alternate days, then every 2 days and so forth. Sound sensible?
It sounds sensible, except rather than stick to a routine,such as strict water changes every 2nd day, I would suggest going off what the water parameters say. But even so, if all goes well, you should definitely be able to follow a routine that is similar to that in the least.
Thanks Ian! I’ll write a report in a bit 😉
P.S. I was wondering, how often should we take out and clean aquarium decorations? They don’t look gunky at all and we hardly ever do lol.. And then when we do, we’re very “tender” about it, as we envision entire families of beneficial bacteria growing on them! Please advise how often and how we ought to do it really!
It all depends on the rest of your maintenance routine. If you are performing water changes, regularly vacuum your tank, and keep an eye on water parameters, then rarely. If you are my niece, who hates the little maintenance she already has to do, then never. Both of these are fine. Because of how decorations are sealed, there isn’t a whole lot of surface area for beneficial bacteria to cling to so cleaning them won’t have any real impact on the balance of your tank. The filter should be the primary home – allowing you to remove bits and pieces and rearranging your tank as you choose without crashing your cycle. The only reason you would ever clean them is if they begin to lose their sheen/detail due to grime and gunk eventually clinging to them and that’s a personal choice. I actually don’t mind how decorations appear to “age” as the tank progresses, but that’s my opinion. Everyone is different and that’s cool too. I guess what I’m trying to say in a rambling way is that it’s up to you.
Hi Ian,
I’m a beginner aquarist and was impatient. I have a 10 gallon with some small fish in it/ I’ve been charting daily water tests multiple times a day to see how things are going. I’ve been doing some water changes and using Seachem Stability and Prime to help with the nitrogen cycle.
I think because I’ve been adding stability my cycle is a little wonky. I’m nearing the end of week 2 and my current numbers are Ammonia at 2.0, nitrite at around .5 and nitrate at around 10. So far, everyone is alive and some of the fish even had babies. I’ve been making upogrades to the tank as I can (better power filter and lighting for the live plants). I’ve been doing a lot of research and am just not sure about water changes at this point. I was steady on Ammonia levels at about 1.0 since Jan 8 and now i’m seeing an increase. I’m feeling like I should do a water change to clear it. I just a water change 2 days ago when I hit 2.0.
After reading your website, I added a bit more prime to cover the combited ammonia and nitrite levels. Any suggestions on what to do? Water change? Keep testing and adding prime? cross my fingers and pray to the aquarium gods?
Thanks so much,
Christina
Hi Christina,
When you changed the filter, you might have caused your cycle to restart (did you keep the old filter running, add filter media to your new filter or remove it completely?) It’s possible this is the cause for the raising ammonia levels.
Even so, the fact you see nitrite and nitrate is promising. You can either use prime or water changes to keep ammonia down, or even both. And yeah, when we do a fish-in cycle, we all pray to the aquarium gods, because even if we do everything perfect, there is still a chance the fish won’t make it. It’s a depressing part of the hobby.
Id personally do a 50% water change, to get your nitrate back down from 5 ppm, and keep monitoring from there, either using prime or a water change to keep things low.
Based on what you are saying, besides the setback, everything seems to be progressing as usual.
Ian,
I changed the filter pretty early in the process. I changed the filter about 3 days after adding fish. I started the stability the day before I changed the filter so I figured since it was so early I wouldn’t lose much.
So in the last five days, I did one water change, about 30-40% with no change in nitrates. It’s been pretty constant at about 10 since I started recording numbers on paper which was on 1/6. I’m using the API test tubes but sometimes I find determining the colors to be tricky. I always read the test tubes in the same place under the same light. Any suggestions on reading the test tubes?
I just did about a 40% water change about 40 minutes ago. Filter is running on full speed to help circulate the water. I added a dose of stability and prime in with water change to make up for the fact. I also tried to really hose up some of the left over food. I think part of the reason is I was experimenting with tablets. I have one bottom feeder (kuhli loach) and I wanted to make sure it was eating too. I’ve been trying to be really conscious about how much food the fish get and when i feed them. I can’t wait till this process is over. This is harder than taking care of my cats!
Thanks,
Christina
For the test tubes, read them outside in daylight, unless you are using daylight light bulbs, (around 5500k) which are not common in homes, you’ll see inaccurate colors. Natural light is best for color matching.
So, on your nitrates, it doesn’t mean your nitrates are at 10, it means they are between 10 and 16 (after this you would probably match it with 20). So if you do a water change and your nitrates are at say 15ppm, a 30% water change would get it down to 10ppm, which is why you won’t see a change. This is worsened once you get to the 40-80 or 80-160 range. So once nitrate levels get up there, I suggest water changes to bring them down, so you can see the rate at which they are increasing. Also, I’d suggest testing your tap water, prior to adding it, so that you can see if there is a default level of any parameter there. It’s not uncommon for tapwater to have detectable nitrate levels. This all just paints a complete picture.
In all honesty, it sounds like everything is progressing as normal. It’s frustrating and you may find you have another 2 weeks or even longer before it looks like it’s wrapping up. But after that, it’s smooth sailing!
Also, I get what you mean with your cats! It’s funny how lots of parents get “fish” as a first pet for their kids, to show that they are ready for pet ownership – fish are a lot harder to keep alive than a dog or cat in the way that you don’t need to know chemistry for these four legged pets – can you imagine explaining cycling a tank to an 8 year old?
Thanks so much, Ian.
Before I found your site, I had ordered a free ammonia vs a total ammonia test from seachem. It came last night and I ran the test. If I read the test correctly, I have little to no (>.02 ppm) of free ammonia. Total ammonia was off the chart. So I figure I’m doing pretty good with the cycle like you said. At this point it’s just trying to keep these nitrates down. My nitrites haven’t fully colonize. When I do a water change, I see the nitrites showing the most change.
So far still have all my fish!
Thanks again,
Christina
Hi Christina,
That’s fantastic to hear. It sounds like everything is progressing smoothly. Unfortunately, it’s a process that just takes time. Hang in there, it’ll be worth it in the long run!
Hello Lan,
I have been doing a fish-in-cycle for about two weeks now using prime.
The Ammonia hasn’t gone over 0.50 ppm. I have a betta in a heated and filtered 5 gal tank.
The problem I have found is that it is starting to look like my fish is getting fin rot.
Yesterday I did a 50% water change to see if that could help?
How should I go about dealing with fin rot while doing a fish-in-cycle?
Thank you,
Kim
Hi Kim,
There was another commenter further down, Catherine, who experienced the same – dealing with fin rot for her betta while cycling. She found success with daily water changes along with following this guide. You could read through that exchange for more info. It’s a tricky one since for fin rot, you want to keep the water as pristine as possible, but to cycle, there also needs to be a degree of ammonia.
Hi Ian! Happy new year!
I thought I’d write up a little “report” for you on the “cycling-tank-with-delicate-fin-rot-recovering-patient” before I forget haha…
So as I’d mentioned previously, nitrites finally entered the equation; for the past few days, levels have pretty much remained at ammonia – zero with hint of green; nitrite at 0.25 vaguely bordering on 0.5; and nitrate 10ish. After much thought, we had decided to sort of combine your method with ours – i.e. dosing with Prime, plus partial water changes, every day.
Now prior to all this cycling stuff, when he had been on antibiotics, we had been doing partial 25% water changes for him twice a day, as somehow once didn’t seem enough (fins would show bits of new ragginess). So we carried on doing the two changes plus the dosing. But after awhile, I thought since we’re also dosing every day with Prime, why do we need to do two? One should be enough and would get the cycling going faster right?
Well here’s the interesting thing. I’ve observed that he would be carrying along healing fine for so long as we did the two changes. But the moment we switched to one, he would show bits of new ragginess the next day. And so it seems we are compelled to keep to the two changes plus the daily dosing until he is completely healed (still have about half an inch worth of fin to go) or at least until the tank is cycled.
Which made me start questioning why, despite the daily Prime, this was happening. I can only conclude that 1) his fins, the new regrowth, are just still in a very delicate state and highly sensitive/reactive to *any* toxins and 2) the effects of Prime may actually start wearing off even before the 24 hour mark.
So that’s the report to date. What do you think? We’re also wondering when we should clean his filter, which you know is only about 2 weeks’ old. Part of me feels like it needs a bit of rinse (not because it looks gunky, but just.. because) and part of me feels like we should let it continue sitting for another week or so to pick up more good bacteria. Thoughts? 🙂
Happy New Year!
Thanks for the fascinating read Catherine. That’s great that you identified a technique that is working for you!
I’d be leaning towards the sensitivity as it is generally accepted that pristine water is a major contributor to how well fish heal. If prime wore off before the 24 hour period, it would be very well documented by now, it’s a very commonly used product by beginners and experts alike.
If I was in your shoes, I would keep what you are doing and see if you can reduce water changes once the tank has cycled.
As for the filter, what filter are you using? I tried looking through the comments but I don’t think this was clarified, that or my old eyes missed it.
Haha… it’s sponge remember 🙂 I’d mentioned how we put a few gravel bits in the tube to baffle the current a little. It has to be sponge I think, as he’s a Betta and you know how they are!
Thanks for Clarifying, I answer so many comments from different people that I often get mixed up, especially with ongoing exchanges. For a sponge, unless it looks super gunky, I wouldn’t touch it until after the cycle is over. After this 2-4 weeks with your water change isn’t a bad routine. Some people buy those stackable sponge filters and wash one sponge one week and the other the next. It all comes down to your routine and what you find easiest.
Thanks SO much Ian!
By the way, does 0 ammonia ever look truly yellow? Like um…a yellow raincoat? Or, to put it another way, does a vague hint of green signify that we’re still not there yet?
http://stuff.iorodeo.com/docs/ammonia/api.html
Describing colors is hard, right? Check this link out, it gives you a good visual comparison. It might not be perfect depending on your computer or phone screen (say if you have night mode on) but otherwise it should give a good idea as to what to expect.
Aw thanks. Zero does look distinctly yellow…pee-ish really haha… OK we’ll keep aiming for that. When the tank is cycled, it should stay consistently that right? Even after say a week, when it’s time for a partial water change?
Yup, your ammonia should stay at zero once your tank is fully cycled. To put it simply, the beneficial bacteria should eat this and nitrites as quickly as they are produced. So quick, in fact, that they won’t show in your test. Any measurable parameters here will clue in that something is amiss. The only parameter of the three that should steadily increase is nitrates, that are then reduced through the water change.
Thanks so much Ian!
How often do you clean the gravel? With every water change or once a month or..? We’ve heard lots of conflicting views on this!
I personally do it with every water change. A gravel vac siphons water so you might as well give your gravel a suck while you are at it. It’s not even an extra step. Depending on your bioload, how much you feed etc you don’t have to clean your whole gravel. If you do weekly for instance, you can do half one week and half another. It’s another one of those things were you “do what works for you and your schedule” I mean, if you don’t have the patience to do it every week then once a month is much better than going months without doing it. As always, testing your water parameters will clue you in as to whether you should be doing it more often.
At first, you’ll likely struggle to clean your entire tank with a single water change anyway. These things take practice but eventually you’ll be gravel vaccing like a pro.
Thank you so much!
Hi Ian! Quick question please! We’ve never had a sponge filter before (ours is similar in concept to the Hydro one you mentioned); how do we clean it? Betta’s filter is one month old today and I think we have to clean in? As you know we’ve been trying to grow a friendly bacteria family on it haha.. So today it’s a month old but doesn’t look gunky or anything; just feel we need to clean it on principle? (we clean our Gup’s filter once every couple of weeks and theirs *does* look gunky). Do we have to pull off the sponge or something? Scrub the tube? We needn’t be too vehement about it all, right?
If your tank has cycled, then cleaning is simple:
Grab a bag (I use those ones that your fish come home in from the petshop) and fill it with enough tank water to cover your sponge filter plus a little more. Squeeze the sponge filter and work at the surface with your thumbs, rubbing to remove trapped detritus. Empty the bag, refill and repeat. 2-3 times will do it.
It doesn’t matter if water that comes out is still slightly brown or your sponge filter is discolored. You just want to remove the stuff that is clogging it.
If it doesn’t look gunky yet or your tank isn’t cycled yet, you can hold off. This filter isn’t so much providing mechanical filtration to your tank as it is biological filtration – in part thanks to the reduced flow. So, it shouldn’t gunk up as quick as your other filter.
Thanks so much Ian! No, it doesn’t look gunky AND his tank *still* isn’t cycled (ammonia and nitrite just hovering at 0.25; don’t even bother with the nitrate for now); we’re already accepting that his will take awhile because of the daily water changes. So we shan’t clean today — I guess just wait till his tank is cycled and/or the filter looks gunky?
Spot on. For now, you don’t want to do anything to disturb the colony of bacteria. You want that stuff to accumulate. I’m glad to hear you are being patient with the process 🙂
Hi Ian! Not quite related, but have you ever heard of/used Boyd Enterprises Freshwater Vitachem? Thoughts?
No personal experience, but I have spoken to people use it as a “daily supplement” and claim their fish are happier because of it. Anecdotal of course. Me, I’m dubious of anything that claims to be a “complete vitamin supplement” given there are thousands of different species of fish, with very different needs. I mean it’s benefits, such as fish coloration are better achieved though proper diet rather than feeding poor quality food and using this for color. All-in-one products generally have more marketing appeal than they do practical use. The problem with many of these products is that they are not used in isolation of other solutions, and I have often seen benefits miss-attributed to the product instead of the additional measures taken, such as improving water quality and an improved maintenance routine. I assume you want it for the claims of fin regrowth? Checking out the ingredients, studies suggest the included amino acids help promote overall growth of fish in aquaculture (add weight) I’m not sure where the claims of fin-regrowth come from. I couldn’t find any studies referencing any ingredient in particular relating to fin regrowth in isolation.
Thanks so much Ian. Yes, it was mentioned (anecdotally) by a friend who felt it really helped her Betta’s fin regrowth. Of course she was doing the water changes too, so… I guess it doesn’t hurt. Someone else mentioned Seachem’s Stress Guard, which I do set more store by. I read somewhere once that their fin regrowth is sometimes like a “one step forward, two steps back” affair, and I think it’s sort of true. The past couple of weeks he had no new ragginess — the longest he’s gone — and then this morning he did, which we can only attribute to our water changing a slightly lower percentage the past couple of days (ammonia’s at 0.25). So it seems like we MUST keep to the 25% we’d been doing previously.
Oh these things definitely take time. If you are seeing noticeable improvement with your current routine, albeit slow progress, I’d just keep doing what you are doing. I get the appeal of looking for that “silver bullet” but I think even if these extras were to help, the whole progress will still be a test of patience – your fish is essentially regrowing a piece of it’s body. That’s a huge process in itself. Every instance I have seen of fin regrowth, except in really minor cases, has taken months. While YMMV, the big thing to remember here is that it’s going to take time and patience.
Sorry Ian to be bothering you with yet another question. I was wondering (and please excuse my ignorance!) — if we dose 100% daily with Prime, does that bind up the ammonia/nitrite such that there isn’t any for the beneficial bacteria to “eat” and “grow on”?
With our older gup tank, I think it got cycled (with the fish in) through our almost daily 25% water changes, dosing only the fresh 25% volume of water with Prime and Quick Start each time. We tested every day till it got to the levels they are now. Could I please ask in what ways is that method inferior to yours? Sorry, I definitely don’t mean to imply that you method might in any way be “inferior”! I just really want to understand how it all works! Thank you so much!
All good Catherine, I created this site to help others to the best of my abilities 🙂
Nope, these chemicals are still able to be chowed down on by bacteria, even if treated with prime. If you experience an ammonia spike in a cycled tank, part of the reason we treat with prime is to give the bacteria a chance to catch up while keeping it harmless to fish.
If you google, there are hundreds of different ways to cycle your tank. None are inherently wrong. In the same light, no-one could argue that their method is superior either – if you reach a cycled tank using a method that was easy for you, and achieved the same result, then that was the best way for you to do it.
With that said, I do not have the opinion that your method is perfectly repeatable. Only treating the 25% may not work if you have fish with a high bioload (say a messy eater or one that poops a lot). In this instance, more ammonia may be produced than you have dosed for. That’s not to say that what you did was wrong, it worked for you and that’s fantastic.
This method is what works best for me. I find it to be repeatable, regardless of what goes in the tank. This is good for beginners, as it helps to narrow down things that can go wrong. If followed correctly, it also allows me to more easily advise as to why something has gone wrong, in the worst case, since I am very familiar with the entire process, since it’s the one I have personally used.
Also, no need to apologize – questioning and challenging is how we learn. Heck, if I don’t have the answer than I’ll go and find it for myself, so I learn too! After 30 years fishkeeping, there are still things I learn – Just last week was the first time I had to treat a case of anchor worms. Definitely not something I knew how to treat off the top of my head.
I guess what I am trying to say, in a rambling way, don’t stop asking questions 🙂
Thank you SO much Ian!
We’re pressing on with the cycling — ammonia still at the same 0.25ish level and zero nitrites/trate. Perhaps one Betta takes a little longer to get things going compared to a little family of gups and cories.
We will perhaps try the marimo — after quarantining it for 2 weeks haha
Thank you so much again; I truly appreciate your time and patience <3
Hi Catherine,
The worst thing about cycling is that it takes time. When comparing day-to-day,the process seems frustratingly slow. I highly recommend recording your daily measurements, so that you can see that progress is indeed being made. If you have excel skills, you can create a line graph to help visualize the progress. The big thing here is patience.
My only suggestion would be to grab a filter, if you have not already. A small sponge filter will do – it will give a good place for your beneficial bacteria to build themselves a moveable home (you can transfer it to another tank to make cycling much quicker if you need to etc.) I prefer the “hydro sponge” brand but in all honesty, anything will do.
Oh Ian, we’re so sad to observe that Betta is just now showing some new ragginess/loss on a bit of his tail when we did his water test today.
Ammonia is still 0.25ish and zero nitrite. As previously mentioned, we had been doing partial water changes every day prior to introducing his new filter 5 some days ago, adding Prime for just the new water with each change. Since starting this cycling was the first time we stopped doing it every day.
His tail had been growing back nicely, slowly but surely, and today this — not sure what to do/what it means :((
Oh yes, we are recording every day and yes, he does have a small sponge filter. It has a similar structure to the Hydro-sponge I believe, but we put a few gravel pebbles in the upright tube thing (out of which the bubbles come) to baffle the outflow/turbulence a bit. Is that bad?
A better way of doing it would be to add a bleed valve to your air pump line, (a connector piece + a flow control valve) this will allow you to control the air flow without blocking off the sponge filter. Open the valve wider to reduce the current. This will keep the current that flows through the sponge constant, rather than potentially blocking off areas.
Regardless of progress, a fish-in cycle is tough, especially on a fish that is already sick. There is never a guarantee that your fish will survive, regardless of how you cycle. It’s possible the cycle and other stressors are responsible for the new rotting areas, assuming you have confirmed the fin-rot isn’t a secondary symptom of another disease, either bacterial or fungal. It is also possible that the fish has non-noticable symptoms of other diseases or even parasites that are stressing it out, and despite your best efforts, it was too far gone from it’s previous home to be saved. Unfortunately, sometimes these things are out of our hands.
The best solution would be to move it to a tank that is already cycled water quality often plays a huge part in how quickly fin rot progresses and in a non-cycled tank, it can get dicey. Do you know anyone who has a hospital tank you can use in a pinch?
Oh, I just saw the last part of your reply (odd; how did I miss it haha) — “The best solution would be to move it to a tank that is already cycled”…
Well of course our other tank is cycled, but I don’t want to imagine Betta and Gup together haha… We do have an extra smaller tank, about 1.5 gallons.
Thank you so much Ian. We will keep hopeful and doing our best for him! He is very sweet — we will update you in a few weeks on his recovery 😀
Have a wonderful Christmas season and thank you so much again for all your help!!
If the extra small tank is cycled, It could potentially be a viable solution, even though it is certainly too small, I would strongly consider the tradeoff vs pristine water. Unfortunately, this is a judgment call that only you can make. Whether you do or not, you are not wrong. You are just doing what you believe is best. This would also free you up to fishless cycle your current tank, which is much easier. Of course this advice is all for nought if the tank isn’t cycled. Some independent pet stores sell pre-cycled sponge filters, which can reduce a cycle down to near instant (up to a couple of days), but these stores are few and far between. Just listing ideas as they pop in my head.
Otherwise, just keep doing what you think best. It’s clear you have your head around testing and cycling, so if you feel it’s better to mix things up then go for it. My advice in this guide is for beginners who are not cycling with an already sick fish, so if you have a better solution, roll with it.
I hope you have a merry christmas and, if I don’t hear from you before then, a happy new year. All the best and I’m sending your betta my well wishes!
Thank you so much Ian. Nah, the smaller tank definitely isn’t cycled — it’s empty and dry on a shelf! Betta’s adoption was unexpected — he had been dumped at our vet’s where we were actually with our dog that day.
I think we might have to cycle his tank the way we’d done with Gup’s — the daily small changes — because I’m presuming in his healing state he’s just very sensitive to any ammonia or whatever. Gup’s tank was helped by the presence of an active filter the whole time (and possibly the marimo) so now hopefully the presence of the new filter in Betta’s tank will help things a bit. It’s not as “powerful” a filter as Gup’s, so we’ll see. Fingers crossed!!
You are an angel for grabbing the Betta and attempting to give it a better life!
It sounds like a good plan. I can’t fault it. Please keep me updated with how it all goes, or if you have any more questions, drop me a line! All the best!
Hi Ian! Hope you’re enjoying the holidays!
I was wondering — how often should one give the whole tank a wipe-down, including the floor? To do that would of course necessitate removing everything in the tank, including fishy, which as I understand it, we shouldn’t do too often?
I don’t mean really obvious scum and algae. But some time back, I noticed a sort of clear, but shiny/slimy quality to Betta’s floor, so decided to clean it. Sure enough, it felt slimy, but came off easily and still hasn’t returned since. It was on the walls to some extent as well, but not really much. I figure it’s some sort of scum thing that naturally forms after awhile in a wet environment, like on bath tiles, so was wondering how often/imperative it is that I clean this stuff off. Thank you!!
p.s. You may be interested to know that Betta’s tank is finally showing a bit of nitrite!
Hi Catherine,
There isn’t really a hard and fast answer here, some people wipe down the walls every time they water change, others only wipe down when their view starts to become obstructed by scum and algae. As long as your water parameters are normal, you can do it as often as you need.
As for the gravel, I suggest grabbing a gravel vac, this device will clean your gravel as you change the water at the same time. I consider it an essential product as poop and uneaten food can fall into gaps in the substrate and turn foul. If you want a good one, check out my reviews section, I have personally tested over 40 different types and stand by my recommendations.
Both of these can be done with fishy in the tank.
It sounds like you might have been dealing with diatoms (brown algae) these are common in new tanks and often go away on their own.
Also, that’s awesome to hear about your progress!
Unfortunately, while I can combine comments, I can’t move them outside of their replies, the software I use does not have that functionality. You’ll need to create a new comment.
Yes, those strips are really unreliable I think. Do you know — the ones by Tetra — for the longest time they didn’t show up any nitrites or nitrates (for our gups at the time) and said our ph was way too low! It was only later with the liquid tests that we saw the nitrites/trates and learnt our ph was 7.6.
Oh by the way, I forgot to mention that in conjunction with the Prime, we had been using API Stress Coat to help with his fins. I think…… it …. helped… ? (“the healing power of aloe vera”!) Shall we continue dosing it with the Prime? And what about the Quick Start?
Another question — do you have any thoughts on marimo balls,the (ideally) genuine ones? We had one in the gup tank and I think that did help with the whole cycling thing. Now we’re wondering whether to add one into Betta’s tank — just a little uncertain whether that would be a good thing (in light of his fin issue). Thank you!!
Unfortunately, your experience with test strips mirrors that of many others, they are not accurate enough to rely on their results.
I have no experience mixing prime and stresscoat together, most people either use one or the other. I believe the only difference is that stress coat contains aloe, however it’s up for debate as to how effective aloe actually is. Prime also claims to stimulate the slime coat, so the theory goes you should be able to swap over to just prime without issue – it does more and is more concentrated.
Quickstart or any other bottled bacteria may or may not help speed up the tank cycle. In addition to the bottles containing different strains of bacteria, depending on the brand, they can also be dead on arrival. These bottles contain a living thing and if it’s no properly stored (too old, too hot or too cold), say it gets frozen in transit, then you are just adding dead bacteria to your tank. Unfortunately, there is no way to guarantee your bottle is alive. With or without bottled bacteria I have seen many tanks cycle both in under a week or over 2 months.
A marimo moss ball shouldn’t make a noticeable difference in an aquarium cycle. The “live” moss balls should be quarentined before being added to your tank though, they can introduce some unwanted stowaways.
Hi again Ian, more on our Betta saga 🙂
There isn’t any new ragginess on him thankfully, but we just did a water test and the results are curious — ammonia was 0.25 (with a hint of yellow) and nitrite was 0. So I was expecting nitrate to be 0 again, but now it’s definitely bordering on 5.0. What does it mean?
And p.s.– what would be a good length of time to quarantine a marimo ball? Thank you so much!
Hi Catherine,
That’s awesome news on the fin rot!
As for the nitrate, it can mean one of two things:
1. The second beneficial bacteria (nitrite ->nitrate) has appeared and is quickly converting nitrites to nitrate, so quick that it’s keeping your nitrite reading at zero. Sometimes this can happen before the first beneficial bacteria (ammonia ->nitrite) has established itself to the extent that it can process ammonia just as quickly.
2. Your tapwater actually contains nitrates. 5ppm is within the range that some water sources contain. You can eliminate this as a possibility by testing your tapwater prior to adding it to your tank. If your tap water contains elevated levels of nitrate then you will actually introduce this to your tank with each water change. You might want to take a reading of this 3 times over a week (say, Mon, Wed, Sun), just in case. Of course, by then your cycle will have progressed, but it’s always good to know the exact parameters of what you are adding to your tank.
Depending how paranoid you are, 2-3 weeks for quarantining.
Three weeks then haha
Hm ok I’ll test the tap for nitrate. Though it’s been zero for the longest time prior to this, so that would be interesting… I know the tap *does* have ammonia though :/
If it’s the first scenario, is that a good thing?
If it’s the first scenario, it suggests that your cycle is progressing as normal, which can only be a good thing 🙂
Sigh it looks like the second scenario — the tap water has nitrates at 5. What does this mean for Betta’s whole cycling thing and how should we proceed please?
Thank you so much.
I’d start by confirming that you are testing correctly.
Follow each instruction piece by piece to make sure you are not missing anything, and be generous when it asks you to shake.
Next, read your results under daylight. So go outside if you need to and look at the test. The lighting in your room can throw these off dramatically.
Now, you want to measure your:
ammonia
nitrite
nitrate
pH
Temperature
How long it’s been since you started your fish-in cycle.
How long it’s been since your last water change
How often are you doing a water change
And list everything else you have in your tank, no matter how minor.
Once you have confirmed these basics are correctly listed, I can give you better advice on how to proceed.
Thanks Ian. Do you mean test the untreated tap? Or the treated tank water?
I’m pretty sure we’re doing the tests right and the treated tank water currently is ammonia 0.25ish (with hint of yellow), nitrite 0, nitrate 5, pH 7.2ish
The pure tap is ammonia 0.25, nit 0, nitrate 5, pH 7 (perhaps 6.8ish)
We don’t bother with temperature for our tanks anymore as we live on a tropical island and it’s perpetually between 25 and 30 deg c. We used to use a thermometer but it just sat there pretty much at 25.
> How long it’s been since you started your fish-in cycle.
Well as you know Betta was on the antibiotics and all that, so I’d say this whole trying to cycle him thing really started Dec 4th. He only has his sponge filter at present as his previous marimo was chucked and trying to keep things fairly pristine while he’s healing.
Okay, so if there is only a sponge in the tank, and recently, then this is the only place that bacteria can call home – so it was an essential addition.
So the ammonia in your tap + tank is 0.25. When was the last time you performed a water change?
I only ask because it shouldn’t take long (a few days) for your betta to increase the amount of ammonia in your tank. If you are doing your daily water changes like you suggested, then it’s all waiting game until you see nitrite increase.
Yikes on the spring water, it’s expensive enough to drink much less house a fish.
You know what I think accounts at least partly for the earlier zero nitrate readings was that he was still largely on spring water. The vet had suggested using that during his antibiotics course because of the ammonia in the tap water. When he finished his course, we started very gradually increasing the amount of tap water, and decreasing the spring, because really — spring is expensive!
Yes, the filter was definitely an essential addition. We’re hoping to get marimo back in (after the 3 week quarantine haha) The last time we performed a change was today; basically 25% every day because of the healing.
> Yikes on the spring water, it’s expensive enough to drink much less house a fish.
You bet. Hence the very gradual reverting to tap!
Do you think TWO partial changes a day — say morning and night — would be beneficial or unnecessary, in terms of his healing?
On the water changes, It would depend on how quickly ammonia, nitrite etc. rise. Ideally, there needs to be some of these chemicals in the tank for the beneficial bacteria to form. I’d perform water changes to your testing, rather than following a rule of two no matter what.
> I’d perform water changes to your testing, rather than following a rule
Yes, agree. Perhaps in addition to the routine morning testing during this healing time, we’ll test again at night, just to see where things stand at the end of the day, and take it from there. Thanks soo much again Ian — we’ll keep you updated (if you like haha); perhaps our experience will add to your arsenal of knowledge 🙂
That sounds like a great idea. I’d love to be updated, it will allow me to better help someone else in the same situation, should it arise! Thanks Catherine. I hope you have a merry Christmas if I don’t hear from you earlier.
You too!
Hi there,
We rescued a Betta with fin rot. In the early days, because his torn fins were so fragile, we kept him in his tank (about 2.7 gallons) without a filter (thought the current might affect them). He went through a course of antibiotics while doubtless killed ALL bacteria. After the course, his fins were still fragile and raggy, so we held off on the filter and did partial water changes daily. The ammonia remained at about 0.25 and zero nitrites and nitrates. We use Prime and API Quick Start.
Now happily, since his fins are growing in nicely, we got a new filter in for him. It’s been 2 days with the filter and the ammonia looks somewhere between 0.25 and 0.50 (so hard to tell with the thing) while nitrites and nitrates remain zero. Now I’m not sure how to proceed – at least some percentage of the tank water is still protected by Prime, while presumably some of the earlier Prime has already worn off.
We did 25% daily water changes because the presence of the ammonia upset us, but I think now that we should actually do them every 2 days instead to give the beneficial bacteria something to live on? So do we just start dosing with Prime for the ENTIRE water volume? How often should we do water changes during this cycling period, and how much? Help please!
Oh, and by “one dose” or “double dose” of Prime, do you mean one dose for the ENTIRE volume each day, or — in the case of “double dose”, two doses each day — say, one in the morning, one in the evening? Thanks so much.
Hi Catherine,
Thanks for being an awesome person and rescuing a Betta!
A double dose refers to doubling the amount required to treat all the water in your tank in a single time. Don’t spread it out over the day.
If nitrites are zero and nitrates zero (or low) then you are right at the start if the cycle.
As for water changes, the Seachem Prime is binding the ammonia, so as per instructions above, we try to keep it at 1ppm, and perform a water change when it hits 2 ppm (50% will cut this roughly in half to 1 ppm). And keep dosing.
How how often you change the water over is a judgement call according to your tank. You’ll need to base it off your own test readings.
You are dosing for the entire volume of water because your fish is constantly producing ammonia inside the tank, and it’s not a controlled amount.
Thanks a million!!
So we keep putting in new Prime every day right (at 24 hour intervals)? whether or not we do water changes? Is there a possibility of overdosing (I mean where there’s just “too much” Prime in that same body of water)?
On a side note, do you agree that Bettas *should* have a filter? Some people told us they didn’t need one; in fact the people we rescued him from were doing 100% water changes every 3 days….
P.S. I asked about the filter also because his fins are still growing back; he’s not 100% recovered yet. I imagine that would take at least a month more, but we didn’t think it would be good for him to go without a filter the entire time. Was this wise? Or should he perhaps wait till his fins are totally restored?
Thank you so much!
It doesn’t have to be right on the 24 hour interval, prime detoxifies for 24-48 hours. However, I would suggest doing it closer to the 24 hour mark than the 48 hour mark – you don’t want to let it get to a point where the prime has worn off.
Seachem themselves state that Prime can be dosed safely up to 5x, so if you are just doing a single or double dose, you won’t get close to the upper limit.
There is lots of back and forth on this. I’m of the opinion that every tank should have a filter. Especially for beginners – it just makes keeping water quality easier to balance.
100% water changes every three days, while harmless (assuming pH temp etc. kept in check), seems excessive. It was likely done to combat spiking parameters. You shouldn’t need to clean your tank this often. That said, a 2.7 gallon is right on the cusp of too small for a betta, I generally recommend a 5 gallon at minimum. Not only is there more room for a heater, filter etc, but the more water the easier the tank is to manage. Ideally you would want to get away with performing a water change every week or two (it soon becomes a chore) and a larger tank, correctly stocked, will allow you to achieve this. You should perform your water changes to your parameters – once your tank has fully cycled, and you see your nitrites getting excessive, it’s time to change the water. Whether that’s after 1 day or 1 week will entirely depend on a multitude of factors.
Betta hate water movement so regardless of his fin condition, you don’t want to generate too much current. A small sponge filter or careful positioning of a return flow can help keep water movement to a minimum.
I know this was somewhat disjointed, I’m currently on my phone. If you need further clarification, let me know!
Thank you SO much! We just gave him his dose of Prime for the day 🙂
We have another older tank (gups, corys) that I think is pretty much cycled — ammonia/nitrites down to zero and nitrate 10; at this point we can just keep to the routine partial 25% water changes once a week or so right?
Ought we to keep testing the water just to see when ammonia/nitrites reappear to get a better sense of how often we should be doing the changes? How often should we be testing for ammonia/nitrites in a cycled tank really?
Spot on, Catherine – your older tank is cycled so you don’t need to do this prime every day nonsense. You just perform water changes relative to the water quality. How much you change entirely depends on how quick your nitrates rise. 25-50% is the common rage of water changes that most people perform.
During cycling I recommend testing daily. This will allow you to quickly identify if something has gone wrong (say, you need a larger dose of prime to fix a nitrite spike) Testing is the only way to truly understand what is happening in your tank. If you skipped a day, and something went wrong, your fish will have to wait until the next testing day before you test and identify the problem – by then it may be too late for your fish.
It’s one of the reasons why I recommend liquid test kits over strips – it’s more cost effective, daily testing with strips can soon add up.
Hi, it’s Taylor. I just commented about my 5 Giant Danios but I read the levels wrong.
Ammonia: 0.25 ppm
Ph: still same problem as last time
Nitrite: between 0.25-0.50 ppm, but on the lower side of that.
Nitrate: 5-10 ppm, but on the higher side of that.
Still wondering why they seem so high after I just did a water change, and not sure what to do next. Sorry for two different comments, my eyes are getting worse and worse!
Hi Taylor, it’s possible your tap water already has ammonia or nitrites in it. Have you tested your tap water to confirm?
On the ammonia front, seachem prime can cause a false positive for ammonia since the API tests measure both ammonia (dangerous) and ammonium (harmless) – when seachem prime binds ammonia, it is temporarily converted to ammonium. So while you may have a reading for it, it may not be as dangerous as you think. The only way to tell for sure is to purchase a seachem ammonia kit. Off the top of my head, this is the only aquarium test kit to test for ammonia and ammonium individually.
The nitrites are the case for concern and it’s not unusual for your nitrite levels to reach this high in a day if there is no beneficial bacteria there to “eat” them. You can either use prime or water changes to get it down.
Once those are under control, it’s a waiting game. Slowly you should see your nitrates increase as the nitrites get consumed.
Hi, I am doing a fish-in cycle right now with 5 Giant Danios and a 20 gallon tank. I tested positive for nitrites on Wednesday. I waited until Friday to do a water change because I did not have time to do it sooner, but I used Seachem Prime every day just to be safe. On Friday, I did a 40% water change using Seachem Prime again. Today, Saturday, I used the API Freshwater Master Kit to test my water levels. I came back with: (my temperature is at 75 degrees, by the way)
Ph: I’m not sure how to tell this one: I use the regular ph reagent and always come back with 7.6, the highest possible number. The kit said that if you get 7.6, to always try the high range reagent too to know the exact number, but when I use high range, I get 7.4, the lowest number. How do I know what my ph really is?
Ammonia: 0.25 ppm
Nitrite: 0.50 ppm
Nitrate: somewhere between 10-20 ppm
I didn’t think that my Ammonia, Nitrite, and Nitrate could possibly be that high since I had just done a water change the day before, so I’m not sure what’s wrong. What should I be doing at this stage?
Hi Ian, I just wanted to say hello and wish you a Merry Christmas and Happy New Year. You have been a big help and I feel as if I’ve known you for a long time. The aquarium and fish are doing well, as always thanks for everything.
Best Wishes
Steve
Haha, Hi Steve,
I’d say it’s still a little early for the seasons greetings – I still have not even gotten around to buying christmas presents or setting up a tree. But I appreciate it.
I’m super happy to hear that your fish are doing well. No need to thank me, I love to help others. Besides, you did all the hard work in figuring it out!
Wishing you all the best for the future!
The article is really useful to explain the cycle, but seems an bit too much an ad for Seachem Prime to me… because dechlorinating the tank could be done for free! Just let the water 1 day or 2, that’s all! Boiling it or adding Oxygen could make the waiting time shorter. It’s ALWAYS better to do without shop chemicals if you can avoid them.
A good advice would be to test the tap water. Some people have no heavy metals and crap in their water, so the need of a water conditioner is…zero. While some people have toxic tap water, and they have to add a water conditioner.
Another advice: never trust the petshop sellers. If they are good sellers… they lie.
Hi Li,
Some interesting advice here, but I would suggest it’s aimed at people with experience in fishkeeping rather than beginners, who are the target audience of this cycling guide.
I don’t know about you, but I don’t think it’s particularly feasible. Boiling or storing 50+ gallons of water at a time and carrying it to your tank? It’s unrealistic. For beginners, using a dechlorinator is the easiest and most recommended option.
Same goes for your advice on testing tap water for heavy metals, most aquarium master test kits do not have the ability to test for these.
Finally, I agree that big box chains like petsmart and petco are hit and miss in terms of advice, generally leaning on the bad side. But small independently owned fish stores can be an amazing resourse, particuarly to someone starting out,
Seachem prime is my favorite dechlorinator due to how concentrated it is – it’s lasts longer than others. Also, since it can render nitrites and heavy metals harmless, it is useful in other emergencies. If you find another dechlorinator that works better, for a reasonable price and is commonly available for beginners, I’ll gladly swap out my recommendation.
But I do thank you for sharing your advice.
Hey Li, I read your comments about letting water sit or boiling it. You must have a very small aquarium if that’s what you’re doing. I have a 250 gallon Marine tank and when I do my water changes I’m removing a lot of water. It’s NOT feasible to boil 100 or 150 gallons of water. I really don’t think you know what you’re talking about!
Hi Ian, it’s Steve again. Hope you are well since we haven’t talked in a while. My tank is doing great, fish are healthy and have not lost any. Water chemistry continues to be good with no problems. Tank water cleared up with the use of the 50 and 100 micron filter pads although it still looks a little cloudy to me.
I’m wondering if the Bio Max that’s used in the Fluval filters is putting some particles into the water? I’ve been thinking of using Bio Balls instead since they are plastic. I would appreciate your thoughts about that, thanks.
Hi again Steve,
I’m glad to hear your tank water has improved in clarity. Did you rinse your ceramic media before adding it to the tank? This will get rid of most of the lose dust and rubble that comes from the ceramic grinding against each other during manufacture and transport. I would be concerned if your biomedia is dissolving at such a rate it is putting noticable debris in the water.
I use sera siporax for my media and have not had an issue with clouding. I have also seen other tanks achieve crystal clear water while using cheap ceramic rings, so I don’t feel there is a need to swap over to a plastic biomedia, which IMO is inferior in terms of surface area for beneficial bacteria to live.
Also as an aside, how does the water look with different lighting? It’s possible your lights are making the water look cloudier than it is?
Hi Ian, thanks for your reply. I did rinse the bio media thoroughly before placing it in the filters. I asked the question because when I rinse the mechanical filtration at times I notice small white particles on the carbon bags that are under the bio media. As for the lighting I also thought that may be the cause but I
don’t believe it is because the water still looks slightly cloudy with it off.
Hi Ian, hope you’re having a great weekend. So guess what? I took 5 gallons of tank water and put it in a bucket. Then I rinsed the bio media from both the HOB Fluval 70’s in that bucket then put the bio media back in the filters. There was some small white particles that were in the water. Today the tank is clear and looks like it should. Tomorrow I’m going to do the same thing with the bio media in the Fluval canister. Even though I’m not a beginner as you know I’m still learning every day 🤔. Stay well and as always thanks for your help.
Hi Steve!
I’m doing well, thanks. I hope you are enjoying your weekend too!
That’s very interesting regarding the particles. Thanks for the update, I’m sure someone else will have the same “problem” in the future and I can now suggest this as a cause! Thanks for sharing 🙂
Hi Ian,
I don’t see a lot of mention about “jump starting a tank” with Nitrifying bacteria. I have a 75 gallon Cichlid tank with 12 small Cichlids in it. I’m running a Fluval G6 and right before plugging in the pump, I put a whole bottle of One and Only Live Nitrifying Bacteria by Dr Tim. With 12 Ciclids and 2 Cory Cats, so far so good. Everyone is active, vibrant and eating. I monitor every day and only have trace NH3. I have been placing a packet of Marineland Bio-Spira bacteria in the tank every other day…right at the filter intake so it goes directly to the biomedia. I am a week into the cycle, no fish loss and clear water. I still have my UV filter off but my bio-filter and 2 power heads and multiple air stone decorations are going 24/7. Temp, GH, KH, pH are in normal range for Cichlids. I have done 2 15% water changes and using Prime on water change water and when I detect NH3. I check twice a day. My EC (electrical conductivity on the filter is reading ~900 which is high). Not sure why.
Any other comments?
Hi Michael,
You are definitely braver than me doing a fish-in cycle with that many fish.
The reason why I don’t really cover “jump starting” with bottled bacteria because it can be hit and miss as to whether or not it actually speeds up a cycle. I have some tanks cycle in under two weeks with it added as well as the opposite. I have also seen tanks cycle in under two weeks without it.
You have not listed your nitrite or nitrate readings. Nitrite is as dangerous as ammonia during cycling. Are you monitoring this too?
Hello Ian, Thank you , thank you, thank you! The filter pads came sooner than I expected as I have an Amazon fulfillment center near my home. I put the pads in all 3 filters on Thursday and did a 25% water change. By Saturday the tank looked great. I did change the pads Saturday in both the Fluval HOB 70’s as they were dirty and put clean ones in. I’m going to order some 50 micron pads just to see if they have more of an effect. As always thanks for your help, it’s been a pleasure talking with you. 😀
Hi Steve,
I’m a little jealous of how close you are to an Amazon fulfillment center – my orders never come that quick.
That’s awesome. I’m so happy to hear it. Depending on how gunked up the pads are, you may be able to rinse them in fresh water to extend their use – since you are not worrying about beneficial bacteria in these pads, you can be pretty rough with your cleaning.
Here’s to your new crystal clear aquarium. Wishing you all the best in your future fishkeeping endeavors 🙂
Thank you for all the great info! I have been following your steps after I made a mistake and messed my cycle up from setting up a new Hob filter and not Seeding it with bacteria from my old one. My readings today was 0ppm ammonia 0.25ppm nitrite and 0.5 nitrate. Do you beleave I am on the road to a cycled tank???
Hi Zach,
It depends, if it’s been over a week then sure. If this is your first day then something is amiss.
Hello Ian, I have looked at that site before and I have no doubt you are correct that there are small particles floating in the tank. The filter pads I purchased may not be the correct ones since the packaging didn’t say how many microns they are. I have ordered 100 micron pads from Amazon, just waiting for them. As always I appreciate your comments. I’m going to wait until I get the new pads, put them in and let the filters run for a couple of days before we talk again. Best wishes as always.
Hi Ian, I completed my gravel vac and water change, had quite a bit of waste in the gravel. Waited 1 day and tested the water, chemistry is good. The water still looks a bit cloudy and I’m wondering why. As you said there’s plenty of filtration so I would have expected it to be crystal clear. I’m still waiting for that to happen. If you have any thoughts about that I would like to hear what you think.
Hi Steve,
It’s possible that the pieces of debris that are floating around your water are so small, they are actually slipping through the gaps in your filter pads. This is an easy fix. Simply grab a super fine filter pad (50-100 Micron) like this one and place it after your coarser filter pad. It will trap the tiny particles that slip through and will return your water to a crystal clear state – it beats using chemical water clarifiers.
Also, if the bottom of your tank was particularly foul and kicked up a lot of gunk, you might need to give your filter pads a rinse in fresh water, to remove the excess sludge that has built up.
Hello Ian, thanks for the advice I didn’t even think about that. I’m going to pick up the filter pads today and I’ll reach out to you after the weekend and let you know the results. As always your comments are greatly appreciated.
I hope it all works out for you. Have a great weekend!
Hi Ian, hope you had a great weekend! I think the tank looks a bit better today. This morning I removed the carbon from both the HOB Fluval 70’s and added more microfiber in its place since there is carbon in the Fluval 406 canister which I also put microfiber pads in on Friday. Maybe it’s going to take some time for the water to completely clear. I would like to send you a picture of the tank, maybe you may see something I’m not. Let me know if that’s possible and how to do that. Once again thanks and best wishes.
Hi Steve,
Thanks, I spent some much needed downtime with my fish!
Unfortunately I do not have the ability to receive photos through comments.
However, it will take some time for the filters to trap all the micro particles as long as you bought the right stuff, it will eventually all be trapped. The remaining gunk will settle on the bottom of your tank, ready for it to be siphoned away the next time you gravel vac.
The only other thing it could be is floating algae or bacteria, which will multiply in the tank but that’s a whole other ball game. From what you are saying, it sounds like small floating particles. Algae and bacteria have a much different look. You can see pictures of these in the cloudy aquarium water guide.
Hello, love this site, I now understand the cycling process!
However, please can I ask some advice?
I’ve had my 40l tropical tank for a few years but have never been successful in keeping fish alive in it 😔 I decided that I have probably never properly cycled my tank and so thought I would start again and get it right this time. Twice the heater has overheated the tank and so I made the decision to get rid of it and go cold water with goldfish. I had kept the tank and filter running since the last of my fish died. The pet shop convinced me to get ‘temperate fish’ and so I came home with 4 platies and 2 snails. Then I did my research (yes I know now that I should have done this before getting the fish and am kicking myself that I could have cycled so easily with just food!).
I took your advice and got the testing kit you suggested. The fish were put in the tank 2 days ago and I have completed small water changes twice daily since. So I tested this evening (before my evening water change) and results were;
Ammonia 0
Nitrites 0
Nitrates 20
pH 8.2
Does this mean my tank is in fact cycled?
Also how do I bring the pH down?
Many thanks in anticipation of a response, any advice would be gratefully received.
Hi Laura,
Welcome back to the hobby! I hope you find more success this time round.
I would be hesitant to say that your tank has cycled after just two days. I would continue testing each day and perform water changes if your test results return a reading, for the next week.
As for pH, you can lower pH naturally with indian almond leaves or peat moss. Alternatively, you can use RO water however this will require you to remineralize it before adding it to your tank.
I set up a 75 gal fresh water tank late August. I’m cycling with fish in the tank. I have been testing my water every 2 or 3 days. I have never seen an increase in Ammonia, Nitrites or Nitrates. I was doing partial water changes but have stopped. Water chemistry continues to be good. My tank water has been some what cloudy and has not cleared as of yet. The fish are healthy and eating well. Please help if you can.
Hi Steve,
I would double check your test kit has not expired and isn’t faulty – ammonia won’t take long to build up to measurable levels.
If there is no ammonia or nitrites but nitrates, then your tank has cycled. Given that it has been over a month since you set up, this is another possibility.
Hi Ian, thanks for your reply. I checked my test kit and it is good until 2020. I’m using Tetra test strips and have also had the water tested at the local Pet Smart. I checked my water again today. No Ammonia, Nitrites or Nitrate. I’m really at a loss because this is not my first Aquarium. I had a 250 gallon Marine tank for several years and never had issues. I’m ready to go crazy.
Hi Steve,
Given you are not a beginner, I’m actually leaning towards thinking your tank is cycled and that something is depleting the nitrates. I mean, if there is one thing fish are good at, it’s producing ammonia.
No need to go crazy just yet. If you want peace of mind, I’d take a photo of your tank, write up your weekly ritual and list the equipment connected to your tank and post it to an online aquarium forum – it’s likely someone else has experienced the exact same problem as you before.
Hello again Ian, I appreciate your insight and comments. I’m not very tech savvy when it comes to posting on a forum. I am running 2 HOB Fluval 70’s as well as a Fluval 406 Canister filter. I believe your assessment that my tank has cycled is correct. Today I’m going to gravel vac which I haven’t done since I set up the tank
and perform a water change. I figure the worst that can happen is the cycle process starts over but I don’t believe it will. I will let you know in a few days the results, wish me luck!
Hi again Steve,
Hey, no need to doubt your abilities. If you can comment here, you are more than tech savvy enough to post on a forum!
Given that the vast majority of beneficial bacteria hides in your filter media, vacuuming the gravel and doing a water change shouldn’t have an effect if your tank is already cycled.
Also, that is a lot of filtration for a tank your size. Most would stop at just one of those filters. Not that this is a bad thing at all, more is always better.
I’ll be very interested to hear your results after performing maintenance.
Good luck!
Hello Ian, yes I definitely have a lot of filtration on my tank. I think it comes from when I had the 250 gallon marine tank for 15 years, it also had a lot of filtration. So I did a gravel vac and 75% water change. I tested the water this morning and chemistry is good, tank water looks much better. There was a lot of waste in the gravel that came out. I think I’m on the path finally and can enjoy the hobby again. I appreciate all your comments and help. It’s been a pleasure chatting with you, best wishes.
Hi everyone,
I am new to the aquatic community and I have a 50g tank. I set up the tank 2 days ago and got eager and put some fish inside already. I currently have:
1 plecostomus
1 catfish
1 green tiger barb
2 stripped tiger barb
2 angel fish
2 snails (not mystery snails)
2 black cichlids (temporary)
When I bought everything from PetSmart, the lady failed to mention the nitrogen cycle, so I just put all of the fish in the tank with the water. Today, the tank was cloudy and according to the internet, that’s a bacteria blood, which is good I guess?
Anyway, I went to Petco this time and they were way more helpful.
I just would like to verify if what she said was correct.
The girl told me to remove 50% of the water and replace it with Seachem Prime treated water. Then test it with the API kit.
I just did a test now and the results are:
0.5ppm Ammonia
0.25ppm Nitrites
5ppm Nitrates
Where should I go from here? I only have a 5g bucket to treat and replace the water, so I’m not sure how to dose the Prime since it’s 5ml/50gallons. I have been using a bacteria supplement as well on the first day I received the tank. Should I continue to use the bacteria supplement for every water change?
Thanks everyone!
Hi Vanessa,
You can can work your way through the steps listed in this guide.
A 50% water change is going to take you 5 trips with that bucket. Once you get to tanks this size, I suggest using a water changer instead of siphoning into a bucket – it’s going to save you a lot of time and effort, depending on how far your tank is from the nearest water source.
On the prime question, .05 ml. use a measuring pipette, it will make it easier to precisely dose. Don’t worry if you add slightly more, an overdose shoudln’t harm your fish.
As for the bacterial supplement, there is debate as to their effectiveness. However, there is no reason not to continue with it. If it has been properly stored and within it’s expiry date, it won’t harm your tank.
Your tank is too small for the pleco! Pleco should be put in minimum 79 gallons for one. And they need to be several plecos, not only one, or it’s not a good life for a fish that likes to be in bank to be alone! So it’s not a wonder that you have nitrite & nitrate problems. For the other fishes, I don’t know, but try to get info, because for the pleco, you haven’t been given good advice.
Buy a bigger tank, or give your pleco. Plecos are not good fish to keep in a tank, they shouldn’t been bought, they require too many gallons and family members.
Doing 75% water change is too much, it’s very stressful for fish. It should be done in my opinion only if there’s a big problem with the quality of the water. Most of the bacteria are in the filter, that’s right, but you lower the number of bacteria when you do a water change, they are not all in the filter, there are also bacteria in your soil, and on every surface they can colonize, but a large part is often in the soil.
Hello I am hoping you can help me. I’m at a loss. I just recently started my first tank. We had them when I was little but I was never responsible for them and back then no novice really knew anything about the nitrogen cycle. I started researching early and went to our local aquarium store. On August 10 I set up a 15 gallon freshwater tank using Aqua Life Complete water conditioner. They also told me to get to cheap hardy fish to start my cycle. They also had me add Aqua life activate along with my 2 Glo Fish tetras. There are also 3 live plants.On August 16 more Activate was added. Then I tested using API master test kit on the 22nd. pH was 7.6, HRpH 7.4, Ammonia .5ppm, no No2 or No3. My friend who keeps fish told me to do a 50% water change at this point. I also added a bubble wall. On the 21st I did have some bacterial bloom which cleared up pretty quickly. Tested on the 24th and got these differences Ammonia <.25ppm still no Nitrites and now 5.0 nitrates. Exact same thing on the 28th. I'll admit at this point with my fish continuing to seem healthy and happy and my numbers the exact same, I added 2 more Glo fish Tetras on September 2. Continue testing, some more water changes sprinkled in there and still the exact same numbers. On September 7 I took sample to the Aquarium store and had them test and they got the same numbers and said it of course had no cycled yet so add some more Activate which I did. All 4 fish continue to be healthy and seem active and happy. I had run across your blog
last week and ordered some Seachem Prime to try your method. Yesterday I tested and got all the same numbers. I have also started seeing some visible algae on the decorations so my friend recommend I clean it up since I have no algae helpers yet. So I cleaned some noticeable areas and did a 30% water change using the Prime for the first time, since I was about 1 in low on water from all the testing. I got busy cleaning the house and forgot to empty the test tubes immediately and came back to the about 6 hours later. The ammonia was definitely yellow no more doubt that it had any green tint. Not being a chemist I don't know if that would just happen to any ammonia reading OR if it was a more accurate reading. 24 hours later I just tested and got the same numbers but it does appear that the Nitrate reading comes quicker even though it's only 5.0. I've yet to have any Nitrite reading. Sorry so long winded but I wanted you to be able to have a full picture.
Hi Heather,
Unfortunately, cycling is something that takes weeks and to get a true picture of what is happening you should write down each days results and compare them. If your nitrates are going up, then they have to be coming from somewhere, and it could be that your tank is well on it’s way to being cycled.
Also, I wouldn’t trust any test reading that had been left to sit for 6 hours.
If Aqualife Activate acts similar to prime then it is possible that your test kit is giving a false positive for ammonia, including ammonium (harmless) in the total. As far as I know, Seachem is the only test kit manufacture that tests ammonium and ammonia separately.
Alternatively, you can use a free ammonia calculator like this one (NH3 is ammonium, NH4 is Ammonia) to see what is happening in your tank, However, you will need to know your tank temperature, pH and Salinity in addition to your ammonia measurement. While most saltwater tanks will know their salinity, most freshwater tanks won’t and you’ll need a device to measure this.
The alternative is to leave it a few days, see what happens to your nitrate levels. If you think your tank is cycled, you can skip the prime for 48 hours and re-test.
Thank you. I will get a Sea chem ammonia test kit. Because right now none of my numbers are changing. I know it can be a long process but as you can see I’ve never had a spike of numbers to even think anything is happening. I just feel at a loss. And nothing I read seems to match what I’ve seen happening.
If you have fish in your tank, then ammonia, nitrite or nitrate levels should all be increasing. Ammonia is given off when you feed your fish, when they poop etc, it’s unavoidable and at the very least you should be seeing a change in the ammonia reading after a few days.
That’s what I keep reading but here I am a month into it and nothing’s changed. I test every day. And it’s always the same.
Ok I’ve been dosing with Prime. I tested today and there was definitely no ammonia. Still never had any nitrites. Nitrate color looked paler orange today too. pH is 7.6 and HRpH is 7.4. Tank temp is 80F. Should I just keep dosing with Prime?
Hi Heather,
If you believe there is no ammonia, and no nitrites but your nitrate levels keep increasing, then your cycle is done.
Prime wears off 24-48 hours after each dose (assuming you dosed correctly as per volume of your tank) If you wanted, you can keep testing multiple times through this window and past it, to make sure everything looks okay.
Alternatively, keep dosing and monitor your nitrate levels. If they continue to rise but your ammonia and nitrate stay at zero then you can be confident your tank has been cycled.
Hi
I’m doing fish in cycling with prime as per your instructions, should I still normal weekly water changes through the process?
Thanks
Amy
Hi Amy,
If you find yourself doing a water change before the week is out, there should be no need to perform a weekly water change.
I have a betta in a 5 gallon. First fish ever. Now I know I put him in prematurely, but I am reading as much as I can and testing daily to keep him healthy. I have been getting ammonia readings 0.5ppm on once daily testing (no nitrites or nitrates yet) and have been doing a 30% water change daily (with added water conditioner). Is that too much or too little? I’m wondering since the bacteria need ammonia as a food source and I’m always removing it, how can they really take hold? I did add the recommended bacteria supplement on initial set up.
Hi Amy,
As long as there is ammonia in the tank, beneficial bacteria will eventually begin to establish. Unfortunately, this can be a very slow process. My last tank took me almost a month to completely cycle. Is the 0.5 ppm measurement before or after you are performing the water changes?
Before the water change. I test, then change 30% if I am seeing ammonia. I have been waiting 24 hrs to test again.
It might be worth testing after the water change, to make sure that the levels are not dropping down to unreadable levels. The results you read before the water change might be due to it building up over the day.
I do not know about the cycle and till I buy 20 gallons tank, fish and substrate. I have over 10 fish die gradually. I test my water in pet store, they finally all come out good after 6 weeks but eventually all fish are dead except 2 coral cat fish. I am not using that tank because I want to start over again. now I use a old turtle tank for remaining 1 catfish. it is 10 gallon, I restart the cycle. in beginning the ammonia is very high, then I do 100% water change, it is 4 days ago, now the ammonia around 1ppm. no trace nitrite but about 40ppm nitrate. the tank just set up about a week. should I do another water change again? does my cycle done? I put some water and decoration from a exist dirty 2 liter fish tank with fish inside and add to this new tank. I read on line and says it will help to speed up the cycle.
Hi John,
If you have performed a 100% water change during cycling, then it’s possible that you have removed the all the nutrients needed for your beneficial bacteria to grow, stalling or even restarting the cycle. If that’s the case, you are back to square one and will have to try again.
Thanks, my daughter is planning on taking a fish up to college with her in a few weeks. She decided on getting a juvenile pictus with her. She set up a new tank with a sand substrate since he didn’t seem to like the gravel in the community tank. He loves the sand but she read you should totally replace it every two weeks but wouldn’t that slow down the cycling of this new tank (we added lots of yucky filter juice and quick start to try to speed up this new tank). She tests constantly, and is doing frequent water changes with Prime and Stability. He seems to be happy.
Two questions…the pet store person grabbed the little guy with a net and he was stuck. It looks like he has a fin fracture on one if his dorsal radials. It turned white and he got a little white bump on the fin but everything else looks fine and nothing is spreading. Do you need to do anything to treat it? He is swimming fine.
Second, should she take Sigmund home on Thanksgiving break? It’s only 4 days. I doubt the water temp will drop below 70 even if the RA turns of the heater. I figured she could put one of those vacation bricks in. She thinks it would be better to take him home (3 hour trip). What do you think?
Hi Susan,
Most of the beneficial bacteria lives in your filter. Only a small is found inside the tank itself. If your filter is rated for your tank, properly cycled and your tank isn’t overstocked, swapping out the substrate shouldn’t cause the tank to crash.
Even so, two weeks for swapping over a substrate sounds both excessive and hard work. Most fish keepers I know stir the sand and use a gravel vac to keep the surface clean. Breaking off a prong from a plastic fork and taping it to the end of the gravel tube will allow you to both stir the sand bed while whipping up any gunk sticking on top without sucking up much of the sand.
If it’s a physical injury, all you can do is leave it to repair naturally, paying extra attention to keeping the tank very clean and water parameters normal – there isn’t such a thing as casts for broken fins.
Most well fed fish can happily survive a week and often more without food – in the wild your fish wouldn’t have a regular meal time, and may only come across a meal every few days. Best way to test this is to do a trial run, skip feeding him for 4 days and watch closely to how it fairs. If you plan to go down the vacation block route, do the same – many users report that the block fouled up their water, killing their fish.
I’d still recommend buying an aquarium heater. It’s not the temperature itself that kills fish, but rather the rapid temperature change – the temperature in a small tank can drop and raise quickly, causing stress.
I use products with bacteria in them to get a head start. Works pretty well for me. I also use a product that helps protect fish from nitrite spikes. It helped save my fish when my bacteria colonies died and I had to rebuild them. Plants can also be a good way to keep ammonia, nitrite and nitrate down. From what I’ve read floating plants and those little moss balls both work pretty well. Floating plants can get CO2 directly from the air instead of the water which helps them clean up the water more.
These days I almost never change the water in my main tank due to a large number of plants. I monitor the water closely though.
Hi Katherine,
Thanks for sharing your experience! Sounds like you have a pretty advanced setup – especially if you are able to go weeks without water changes.
Bacteria in bottles or tablets are totally useless. Proving that it makes the cycle shorter has never been done. It’s only to make you give the money. It’s a waste of your money. If you don’t believe me, try to find researches on the duration of the cycle with the all dead bottled bacteria, and without.
I’m currently on my 3rd week of a fish in cycle.
I re-homed 4 danios from a friend who no longer wanted them, and at this point knew nothing about ‘cycling’ a fish tank, or really much about fish, except that new tap water should be de-chlorinated.
The fish lived happily for a little while, then 1 got poorly and died, then a 2nd, and then sadly a 3rd.
At this point I knew something was up and then started to research about coldwater fish, and low and behold found out about cycling.
I basically started again with the last remaining danio. I bought a new tank, filter etc… and started the cycling process.
I have a quick question…. My ammonia levels have lowered over the 3 weeks (currently 0.25ppm), however the nitites and Nitrates are really high, above the acceptable level.
Will regular water changes keep this under control, aswell as allowing the beneficial bacteria to establish?
I add aquarium salts, and some good bacteria, but it seems to be a slow process, and just worry for my last remaining fish.
Any help / reassurance appreciated.
Hi Amy,
Unfortunately cycling your tank is never instant it can take weeks or even months – patience is key. I know this can be hard when you have fish dying before your eyes but hang in there!
It sounds like you are nearing the end of the second stage of the nitrogen cycle. Here is a chart from the last time I cycled an aquarium. As you can see, the nitrites build up before slowly dropping in number as nitrates begin to appear. You are nearly there! To get a greater idea of where you are in the cycle, perform daily checks with your aquarium test kit for ammonia, nitrates and nitrites.
Performing water changes will help keep your nitrites and nitrates down. Just be mindful that don’t want to remove all the nitrites, as your colony of bacteria needs this as a food source. Make sure you test closely.
You got this!
Wish I’d seen this article before I started. Into week five and nitrites just appearing but was ill informed at pet store. Started with 4 fish ( buy 3, get one free). Now have 2. Will know better next time.
Hi Jomardeuse,
Thanks for sharing your experience! I’m sad to say that this is not uncommon. That’s why finding a good local fish store, with knowledgeable staff is essential in this hobby – for a beginner, keeping fish is more complicated than it first appears.