7 Best Oscar Fish Tank Mates (Compatible And Safe)

Oscar fishes are notorious killers and playful creatures – the perfect combination of stunning and troublesome. 

These tropical freshwater inhabitants are not the friendliest and are eager to devour or bully fishes that come their way. So, most aquarists wish to add a bit more color and spark to their aquarium and look for a suitable Oscar fish tank mates.

In this guide, we will look at the fish types that can be excellent tank mates for your Oscar and some species that don’t. So, without further ado, let’s dive right into it!

Can Oscars Live with Other Fish?

Yes, Oscars can live with any sort of tankmate (smaller, less aggressive fish) if you set up a minimum 100g tank. Sorry tank mates and tank size can’t be exclusive from one another.

Do Oscar fish need tank mates? Oscars do not necessarily need tank mates, but keeping other fishes around them can make them more sociable since they are inherently hostile. However, they are highly territorial, so make sure you keep them in a large tank so that both fishes get adequate space to thrive. 

A single Oscar will need a minimum tank capacity of 55 gallons, but that’s rarely recommended since it provides a tiny swimming area. However, as they grow slightly bigger, you will need to shift them to a 75-gallon tank. Some inexperienced aquarists make the mistake of putting another fish along with the Oscar in a 75g tank. This is a colossal mistake and negates the chances of either of the fishes thriving. Remember that for a tank that less than 100 gallons, a single Oscar is enough. 

For a 100g tank, you can have an Oscar with a school of Silver Dollars. However, if you want to keep two Oscars, then you will need a minimum tank capacity of 125 gallons. Usually, unless they grow up together, it is nearly impossible for two Oscars to live side-by-side, given their aggressive nature. 

You’ll need a tank with a minimum capacity of 120-125 gallons if you want to place any large-sized fish with your Oscar. 

Fish to Avoid Keeping with Oscars

Here are a few fish types you need to avoid while looking for an Oscar tank mate:

Too Small

Oscars are hostile creatures that will eat any fish small enough (less than 6-inches) to fit in its mouth. So, always look for fish that is larger than 6-inches. 

Timid or Delicate

An Oscar tends to bully its tank mates, so you need an equally aggressive creature. On the other hand, delicate and shy fishes like Discus need a quiet environment to flourish and will not compete for food with an Oscar.

Small Catfish

Small Catfishes have spines on their fins that will prove to be a danger to the Oscar if swallowed and can kill it.

Fishes That Need Clean Water

Oscars are pretty messy, producing a high amount of Nitrates. Thus, fishes that require pristine water conditions cannot survive in Oscar tanks.

Pro tip: Stick with south American fish, not central American, Central American fish will be too aggressive.

The Best Oscar Fish Tank Mates In A Tank (125g or Bigger)

While looking for a tank mate for your Oscar, ensure the tank is large enough to house both fishes. A Tiger Oscar grows up to 18 inches, whereas an Albino Oscar will become 14 inches long. Therefore, you will need a tank of 125 gallons or more to give adequate space to both the fishes. 

Out here, we have listed the best tank mates for your Oscar. So, let’s take a look!

Ornate Bichir

ornate bichir

Most Bichir species are wonderful tank mates for Oscars, but Ornate Bichirs (Polypterus ornatipinnis) are usually preferred because of their unique eel-like bodies and large size. Native to Central and East Africa, these air-breathing creatures occupy the lower regions of the tank and do not interfere with Oscar’s movement in the mid-region.

Although they are predatory, their targets are usually smaller fishes. Since Oscars are pretty large, Bichirs pose no threat to them and vice versa. Thus, if you choose to keep Oscar and Bichir in the same tank, ensure they are of the same size.

Ornate Bichirs can grow up to 24-inches, so remember to keep them in a large tank with a lid since they are active jumpers.

Scientific Name:Polypterus ornatipinnis
Care Level:Moderate
Color Form:Tan
Temperature:77-83° F
Minimum Tank Size:180 gallons

Gold Severum Cichlid

Gold Severum Cichlid

Bright colored and stunning, Gold Severum Cichlid is more peaceful than any of our other recommendations and can thrive in community tanks. They stay in their territory (usually behind rocks or other tank ornaments) and can gel with different non-aggressive Cichlids, Scavenger Catfish, and Plecos, besides Oscars.

So, if you have a tank large enough to keep more than two fishes, Severums will be a fantastic choice. Moreover, they grow up to 8-inches and are strong and combative enough to stand up to Oscars, if necessary. 

Also, their water parameters are similar, and you can keep the temperatures anywhere between 73-77°F.

Scientific Name:Heros severus
Origin:Amazon, Northern South America
Care Level:Moderate
Color Form:Tan, Yellow
Temperature:73-77° F
Minimum Tank Size:55 gallons

A School Of Silver Dollars Fish

Photo: David441491

Silver Dollars are schooling fishes that swim as a group in the open, thus signaling the absence of any predator. This can be reassuring for your Oscar, who is put at ease and becomes less hostile.

Besides, they have a roundish and laterally flattened body, resembling a silver coin that makes them appear much larger than their standard 6-inch size. As a result, these fishes will not fit in Oscar’s mouth and can easily survive in the tank with it.

Although some Silver Dollars are semi-aggressive, most of them are pretty mellow and do not do well individually. Thus, it is best to keep at least 4 to 5 of them together at all times.

Scientific Name:Metynnis argenteus
Care Level:Easy
Color Form:White
Temperature:72-77° F
Minimum Tank Size:30 gallons

Chocolate Cichlid

Chocolate Cichlid
Photo: cichlid.bros

Native to Southern America, Chocolate Cichlids are easy-going creatures and have the same water and food requirements as Oscar fishes, making them a suitable choice for tank mates. 

They grow over 12-inches long and are exceptionally calm compared to most Cichlids their size. You can keep them in a community tank with most South American Cichlids, Characins, or Catfish. 

It is usually safe to place Chocolate Cichlids and Oscars together since they are nearly the same size and do not threaten each other. 

Scientific Name:Hypselecara temporalis
Origin:Captive-Bred, Peru
Care Level:Moderate
Color Form:Brown, Orange, Red, Yellow
Temperature:76-82° F
Minimum Tank Size:70 gallons

Green Terror

Photo: lkmathew

As the name suggests, Green Terrors are known for their aggressive behavior and metallic green and blue colors. They can grow up to 12 inches, almost the same as Oscar fishes, making the chances of being eaten by Oscars negligible. 

Like Oscars, they belong to the Cichlid species of fishes and can be even more hostile than them, especially during the spawning season. However, the aggression declines over time, especially if the Green Terror is slightly smaller at the start. 

That said, sometimes, these two fish types do not get along, and in such cases, you need to have a backup plan in place. The best you can do is shift the Green Terror to a separate 55-gallon tank. 

Scientific Name:Andinoacara rivulatus
Origin:South America
Care Level:Moderate
Color Form:Blue, Green, White
Temperature:72-80° F
Minimum Tank Size:50 gallons

Firemouth Cichlid

Photo: threefingeredlord

Firemouth Cichlids are hardy and moderately aggressive, preferring to avoid any conflicts rather than facing them headlong. So, make sure you have sufficient ornaments and rocks in your tank to give this creature ample hiding space. Although they usually flee when faced with aggression, they can counter the hostility if necessary.

Since Firemouth Cichlids grow over 6 inches, Oscar fishes can’t eat them. Besides, their food and water requirements overlap, thus reducing the burden for you.

Scientific Name:Thorichthys meeki
Origin:Farm Raised, USA
Care Level:Moderate
Color Form:Blue, Red
Temperature:70-75° F
Minimum Tank Size:30 gallons

Black Convict Cichlid

Black Convict Cichlid
Photo: shutterbusterbob

Another variety from the Cichlid species, Black Convicts are proactive and aggressive. They create a territory for themselves inside plants or caves and often stay here. Thus, they will seldom cross paths with your Oscar fish, minimizing the chances of any conflict.

Moreover, they grow up to 6 inches and hence are unlikely prey for Oscars. Given their aggressive nature, they can stand up to Oscars, when necessary, as long as both the fishes are of similar sizes. That said, we recommend purchasing and raising them together. This will guarantee minimal hostility.

Scientific Name:Archocentrus nigrofasciatus
Origin:Farm Raised
Care Level:Moderate
Color Form:Black
Temperature:68-73° F
Minimum Tank Size:30 gallons


We hope you now have a good idea about the fishes that can live with your Oscar and the ones that can’t.

scar fishes are energetic, intelligent, and easy to raise as long as you provide the ideal living conditions and a spacious tank. Of course, like most other Cichlids, they have a prickly nature, and you need to be vigilant if you choose to keep them with tank mates.

That’s all we have for you today! Remember, Oscars are fascinating and lively creatures as long as you are patient and attentive.

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