Your Oscar may be wonderful to watch on its own, but if you want to spice up your tank with more variety, the question is: what are the most suitable tank mates?
Because of their aggressive tempers, Oscar tank mates should be passive but large enough to avoid getting bullied or eaten by the Oscar, such as the Green Terror Cichlid or the Cichlasoma.
In this article we’ll cover the 15 best Oscar tank mates as well as some FAQs!
Contents
Oscar Tank Mates – What You Need to Know
When it comes to selecting tank mates, there are a few things you absolutely must know, and they are listed below!
Temperament
An Oscar’s temperament is best described as testy! Oscars are territorial fish that do not like to have their personal space invaded, and they are more than happy to chase and even kill any tank mates small enough to cross them and not put up a good fight.
In terms of good tank mate temperaments, what you need is a fish that will be passive enough to avoid starting fights with the fussy Oscar, but not too timid to hold its own if threatened.
Odds are, with this combination, Oscars and tank mates of this temperament will likely be disinterested in bothering one another.
Size
Oscars that are fully mature tend to reach around 12 to 14 inches, making them on the larger size for tank fish. What this means for your tank mates is that they should be at least 12 inches, as well, to avoid being bullied, and large enough to avoid being easily eaten by the Oscar in their tank.
Competition
It may be a fish-eat-fish world, but it is also a fish-eating-others’-food world, too! That’s right; your Oscar is not above stealing the food provided for tank mates who aren’t large or confident enough to compete for their share.
To avoid this, try and find fish that either enjoy a type of food that the Oscar will not be interested in, or pick out fish that can beat the Oscar to their meal and avoid starving.
Parameters; Tank Setup
Oscars need a temperature of around 71 to 84 degrees Fahrenheit when it comes to water, and they need at least 75 gallons of water. When you add more fish, this should be increased to at least 100 gallons.
Consider getting some of the tank mates listed below who can survive in the same tank conditions without getting sick or fighting one another for lack of space.
15 Best Oscar Tank Mates
Check out our list of the best tank mates for Oscar fish!
- Jewel Cichlid
- Convict Cichlid
- Green Terror Cichlid
- Jack Dempsey
- Jaguar Cichlid
- Firemouth Cichlid
- Blood Parrot Fish
- Cichlasoma
- Bala Shark
- Red Tail Shark
- Plecostomus
- Clown Loaches
- Reedfish
- Silver Dollar Fish
- Black Ghost Knife Fish
For more information on why these fish make great tank mates for Oscars, look below!
You might also be interested in:
1. Jewel Cichlid
- Scientific Name: Hemichromis bimaculatus
- Adult Size: 0.75 to 4 inches
- Compatible With: Oscar Cichlid
- Water Temperature: 74°F to 80°F
- Minimum Tank Size: 40 gallons
- Care Level: Easy to moderate
- Origin: Africa
One of the prettiest in the cichlid family is the Jewel cichlid. However, don’t let it’s lovely name and beautiful variety of color fool you; the jewel cichlid is more than capable of using it’s stoic temperament and similarity in size to keep Oscars from bullying.
It is, however, worth noting that the jewel cichlid may become a problem, even for your Oscar, in mating season when tempers are running high.
Pros of keeping with Oscar:
- Too large and confident to be bullied or eaten by Oscar.
Cons of keeping with Oscar :
- Size difference.
2. Convict Cichlid
- Scientific Name: Archocentrus nigrofasciatus
- Adult Size: 6 inches
- Compatible With: Oscar Cichlid
- Water Temperature: 68 to 77 F
- Minimum Tank Size: 30 gallons
- Care Level: Easy
- Origin: South America
Named for the striped pattern that causes this fish to look like it belongs behind bars, the convict cichlid is a great tank mate for Oscar. While they may not look alike, they tend to have twin temperaments, and each fish is likely to find its own space to defend. As long as these territorial boundaries aren’t crossed, they will generally avoid each other.
Pros of keeping with Oscar:
- Large and aggressive enough to avoid being bullied by Oscar.
- Eats a variety of foods, meaning food competition won’t be fierce.
Cons of keeping with Oscar :
- Can become aggressive if there is not enough space for separate territories.
3. Green Terror Cichlid
- Scientific Name: Anidoacara rivulatus
- Adult Size: 6 to 12 inches
- Compatible With: All Oscars
- Water Temperature: 69 to 75 F
- Minimum Tank Size: 75 gallons
- Care Level: Easy Medium Difficulty
- Origin: Ecuador, Peru
The name should give you your first clue as to why this makes a great tank mate for Oscars: green terror cichlids have a fierce personality that can frighten smaller fish! Luckily, in addition to having beautiful green coloration, this fish is typically of a similar size than Oscars and will be just fine as long as each fish has enough room to avoid the other.
Pros of keeping with Oscar:
- Aggressive enough to avoid being bullied by Oscar.
- Eats a broad diet, meaning less competition for food.
Cons of keeping with Oscar :
- Can become aggressive toward Oscars if the tank is too small.
4. Jack Dempsey
- Scientific Name: Rocio octofasciata
- Adult Size: 15 inches
- Compatible With: All Oscars
- Water Temperature: 72 to 86 F
- Minimum Tank Size: 80 gallons
- Care Level: Difficult
- Origin: Mexico
Though this fish’s temperament, large size, and persistence in bullying when kept with just one or two other fish make it hard to care for, there is no denying it is a beautiful choice. Jack Dempseys can be kept with Oscars thanks to their twin aggression, but it is important that there be more than one fish in the tank to avoid bullying, along with plenty of space.
Pros of keeping with Oscar:
- Large enough to avoid being eaten or bullied.
- Will not be chased away from food.
Cons of keeping with Oscar :
- Must be kept with many other fish and not one other Oscar, alone.
5. Jaguar Cichlid
- Scientific Name: Parachromis managuensis
- Adult Size: 26 inches
- Compatible With: All Oscars
- Water Temperature: 77 to 97 F
- Minimum Tank Size: 100 Gallons
- Care Level: Easy
- Origin: Central America, Honduras, Costa Rica
The jaguar cichlid is beautiful in coloration, looking something like buried treasure. Despite the fact that it is only semi-aggressive, it is capable of defending itself if an Oscar tries to start something violent. They also tend to eat invertebrates so competition for Oscar food sources will not be fierce.
Pros of keeping with Oscar:
- Will not be bullied by Oscar
- Will not compete for Oscar’s food.
Cons of keeping with Oscar :
- Can be aggressive during breeding season, even with oscars.
6. Firemouth Cichlid
- Scientific Name: Thorichthys meeki
- Adult Size: 6 inches
- Compatible With: All Oscars
- Water Temperature: 75 to 85 F
- Minimum Tank Size: 30 gallons
- Care Level: Easy
- Origin: Mexico, Belize, Guatemala
If you’re looking to add more color to your Oscar tank, the firemouth cichlid is the way to go! Firemouth cichlids get their name from the way they flare their red gills to intimidate their tank makes. This cichlid is only aggressive when spawning, and otherwise avoids fighting with other fish. The only issue is their size difference. So if the firemouth decides to pick a fight with an Oscar, it might not turn out well for them.
Pros of keeping with Oscar:
- Will not be bullied by Oscar
- Will not bully other fish
Cons of keeping with Oscar :
- Aggressive during spawning time.
7. Blood Parrot Fish
- Scientific Name: Amphilophus citrinellus heros severus
- Adult Size: 12 inches
- Compatible With: All Oscars
- Water Temperature: 75 to 80 F
- Minimum Tank Size: 30 gallons
- Care Level: Medium Difficulty
- Origin: Domestic Hybrid
This fish is not only lovely in color, but adorable, too. This man-made fish doesn’t exist in the wild. It is a hybrid bred for its delightful appearance, parrot-like beak and frilly fins. Blood parrots are peaceful fish, but they grow large enough to avoid being picked on by Oscars.
Pros of keeping with Oscar:
- Peaceful, but will not be bullied by Oscars.
Cons of keeping with Oscar :
- Needs extra feeding during competition due to the formation of the mouth.
8. Cichlasoma
- Scientific Name: Cichlasoma amazonarum, cichlasoma trimaculatim, cichlasoma bimaculatum
- Adult Size: 10 to 14 inches
- Compatible With: All Oscars
- Water Temperature: 74 to 86 F
- Minimum Tank Size: 100 Gallons
- Care Level: Easy
- Origin: South America, Western Mexico
Technically, the cichlasoma is a term that refers to a whole group of fish with many subspecies. Some are intensely aggressive, while others merely hold their own against bigger bullies. Though each species of cichlasoma will try to eat smaller fish, it is similar in size to most Oscars.
Pros of keeping with Oscar:
- Will not be bullied by Oscars.
Cons of keeping with Oscar :
- Aggressive toward Oscars when breeding.
- Aggressive when the tank is too small.
9. Bala Shark
- Scientific Name: Balantiocheilos melanopterus
- Adult Size: 12 inches
- Compatible With: All Oscars
- Water Temperature:72 to 82 F
- Minimum Tank Size: 125 gallons
- Care Level: Easy
- Origin: Southeast Asia
Unlike most of the fish on this list, the bala shark is actually pretty peaceful. It will not start fights, and in fact avoids new fish unless it is another bala shark it can pal around with. Luckily, bala sharks are large enough to make Oscars think twice before attacking. Bala sharks grow large and prefer to be in groups, so you’ll need a large tank to match.
Pros of keeping with Oscar:
- Too large for Oscars to try attacking
Cons of keeping with Oscar :
- None!
10. Red Tail Shark
- Scientific Name: Epalzeorhynchos bicolor
- Adult Size: 6 inches
- Compatible With: All Oscars
- Water Temperature: 72 to 79 F
- Minimum Tank Size: 55 gallons
- Care Level: Medium Difficulty
- Origin: Thailand
Actually a member of the carp family, red tail sharks are not just cool-looking; they are aggressive enough to warn away bullying Oscars. As long as you give a red tail shark some space to defend, including caves, it will be fine living with Oscars.
However, without a cave to claim, red tail sharks might start fights just trying to figure out which part of the tank they want to defend.
Pros of keeping with Oscar:
- Too large and aggressive to be bullied by Oscars.
Cons of keeping with Oscar :
- Can become aggressive in too small a space.
- Can become aggressive without caves to defend.
11. Plecostomus
- Scientific Name: Hypostomuous plecostomous
- Adult Size: 15 inches
- Compatible With: All Oscars
- Water Temperature: 72 to 82 F
- Minimum Tank Size: 75 Gallons
- Care Level: Easy
- Origin: South America
Plecostomus, otherwise known as a plecos, is actually a type of catfish. They are large, making them untouchable by most Oscars, and have the added benefit of looking beautiful next to an Oscar’s gaudy coloration!
Pros of keeping with Oscar:
- Too big for Oscars to bother fighting
Cons of keeping with Oscar :
- None
12. Clown Loaches
- Scientific Name: Chromobotia Macracanthus
- Adult Size: 7 to 11 inches
- Compatible With: All Oscars
- Water Temperature: 77-83 F
- Minimum Tank Size: 100 gallons
- Care Level: Medium Difficulty
- Origin: Sumatra, Borneo
Clown Loaches are adorable and fascinating to watch. They love to play tag and are fast enough to get to their own food before being beaten to it by Oscars. As long as more than one clown loach is in your tank, Oscars and clown loaches will likely get along.
Pros of keeping with Oscar:
- Strength in numbers against Oscars
- Can compete for its own food.
Cons of keeping with Oscar:
- None, as long as it is not the only clown loach in the tank.
13. Reedfish
- Scientific Name: Erpetoichthys calabaricus
- Adult Size: 36 inches
- Compatible With: All Oscars
- Water Temperature: 73 to 86 F
- Minimum Tank Size: 250 gallons
- Care Level: Difficult
- Origin: West Africa
Reedfish are great for visual variety in your tank thanks to their long, snake-like bodies. They can often escape trouble from an Oscar easily, making them optimal tank mates for this pushy fish.
Pros of keeping with Oscar:
- Variance in diet means no chance of starving alongside an Oscar.
- Can escape even the most persistent bullying from an Oscar.
Cons of keeping with Oscar :
- Require a large tank size
14. Silver Dollar Fish
- Scientific Name: Serrasalmidae
- Adult Size: 6 inches
- Compatible With: All Oscars
- Water Temperature: 75 to 82 F
- Minimum Tank Size: 30 gallons
- Care Level: Easy
- Origin: Guyana, Brazil
The silver dollar fish may look lovely, but its main perk as a tank mate for Oscars is it’s sheer size. Silver dollar fish are simply too big for Oscars to bother trying to start trouble with! They are also easy to care for as long as your tank is big enough.
Pros of keeping with Oscar:
- Peaceful attitude means they won’t fight with Oscars
- Big enough to intimidate Oscars away from bullying.
- Wide diet means a lack of competition for Oscar’s food.
Cons of keeping with Oscar :
- None!
15. Black Ghost Knife Fish
- Scientific Name: Aperonotus abifrons
- Adult Size: 20 inches
- Compatible With: All Oscars
- Water Temperature: 75 to 82 F
- Minimum Tank Size: 100 gallons
- Care Level: Easy
- Origin: South America
This fish is simply cool, both to look at and to compare with the Oscar. Black ghost knife fish are semi-aggressive and large enough to keep Oscars from trying to attack. They are also nocturnal, meaning they aren’t even active enough to cause trouble with Oscars during the day.
Pros of keeping with Oscar:
- Nocturnal, semi-aggressive, and large enough to avoid being bullied by Oscars
Cons of keeping with Oscar :
- Very large tank size required!
In Conclusion
In conclusion, the 15 best Oscar tank mates are other cichlids that are of a similar size, or are fish that have matching temperaments. Because the Oscar is so aggressive, finding fish like the red tail shark or silver dollar fish that are big and confident enough to hold their own is the best move.
This doesn’t mean that all fish have to be aggressive. More peaceful fish like the clown loach and plecos can coexist with Oscars just by being big enough to not get bullied! There’s no barrier between you and having a tank with plenty of variety in neighbors for your Oscar.
Frequently Asked Questions
What fish do good with Oscars?
As long as fish are large and confident enough to stand their ground against a pushy Oscar fish, as well as capable of living in the warmer waters the Oscar needs, they will do well with Oscars. Some of these include Firemouth Cichlids, Silver Dollar Fish, and Red Tail Sharks.
Do Oscars need tank mates?
Oscars can be kept with other fish as long as they meet the necessary requirements, but they do not need tank mates to survive or be happy and healthy! Their aggressive temperaments actually mean that they may live a more peaceful life when on their own, although they can be placed with some of the fish on the above list.
Do Oscars prefer sand or gravel?
Oscars are digging fish, and enjoy slurping up and spitting out whatever substrate you give them. They can do this with both sand and gravel, but sand will decrease the chance for digestive blockages if the Oscar accidentally ingests the substrate.
Ian Sterling, founder of Fishlab.com, began his aquarium journey over 30 years ago, driven by a deep fascination for fish and their diverse personalities. His website, Fishlab.com, is dedicated to making fishkeeping accessible and enjoyable, offering beginner-friendly guidance, expert insights, and a community for aquarists to connect and share experiences.