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The Best Tank Mates For Your Oscar Fish

If you already have an Oscar fish, you probably already know this – Oscar cichlids are some of the most fun and entertaining aquarium species you can raise. Not only do they have a bubbly, energetic personalities that make them the stars of your aquarium, but they are also relatively easy to care for.

Unfortunately, Oscars are known for being a bit aggressive – which can lead to problems if you want to keep your Oscar in a community tank.

However, it’s not impossible to maintain a community aquarium with an Oscar fish – you just need to know which species are best suited to living with these South American cichlids. Here are some tips on how to set up a community aquarium when you have Oscar cichlids – as well as the best species for the job.

The Best Tank Mates For Your Oscar Fish

What Are Oscar Fish?

Oscars, also known as Astronotus ocellatus, are cichlids native to South America. One of the largest species of cichlids, an Oscar can grow up to 14 inches in captivity. This fish, which is sometimes called a river dog, has the capacity to form a close bond with its owner and will wag its tail, even – just like a dog!

Unfortunately, as docile as Oscar fish are around humans, they can be relatively aggressive when raised in a tank. As a result, you need to make sure you select your tank mates and the tank itself quite carefully. Opting for a larger tank can reduce some issues related to aggression – try to keep a tank that is at least 75 gallons in size. This is especially important if you are adding any tank mates!

Another tip? Rather than introducing tank mates after you have already acclimated your Oscar to the tank, try adding tank mates first. This will reduce any aggression related to territorial behavior.

What Are The Best Tank Mates For An Oscar Fish?

Just because you have Oscars, it doesn’t mean that you can’t have other fish, too! Here are some of the best tank mates for your aggressive Oscar fish.

1 Severum Cichlid

Severum Cichlid
Photo by Andrei P

Severum cichlids are less aggressive than some of the other fish we will tell you about later on in this article. As a result, these docile, easygoing fish are a great natural choice for your Oscar tank. They get along well with non-aggressive species like silver dollars and plecos. They also make a fantastic addition to community tanks. Only growing to about eight inches in length, these fish are relatively easy to care for and will do quite well with your Oscar fish.

2 Black Convict Cichlid

 Black Convict Cichlid
Photo by Melinda

Ah, the Black Convict Cichlid! This small cichlid usually only grows to about six inches in length, but it is easy to care for and a suitable choice for most Oscar tanks. These fish are tough and despite their small stature, are able to easily hold their own against more aggressive Oscars.

These fish should be kept with smaller Oscars – although convict cichlids can easily fend off attacks from Oscars, placing a large Oscar with a small convict cichlid probably isn’t’ wise. Otherwise, these fish should be able to hold up to occasional chasing or nipping behavior. These fish prefer temperatures between 74- and 82-degrees Fahrenheit, similar to those preferred by your Oscars.

3 Firemouth Cichlid

Fire Mouth Cichilid

Closely related to convict cichlids, firemouth cichlids are also great Oscar tank mates. These fish aren’t quite as aggressive as Oscar fish, and though they are relatively small – just six inches or so – they are very skilled at avoiding and preventing conflicts in your tank.

These fish are more apt to flee than they are to fight with your Oscar fish. As long as you include lots of hiding spots in your tank, which you can create using rocks or caves, these fish will do just fine. They also prefer temperatures of around 75 to 84 degrees.

4 Silver Dollar

silver dollar fish
Photo by David Ellis

Silver Dollar fish are popular Oscar tank mates because they aren’t likely to be eaten by your Oscars. They aren’t overly large, only growing to about six inches, but they are schooling fish that prefer to be housed in groups of four or more. There is safety in numbers when it comes to housing silver dollars with your cichlids. In addition, these fish have unique oblong body shapes that make them appear larger and less tasty for your aggressive Oscars.

Silver dollars tend to swim out in the open. They are known as “dither fish” for this reason. When in a group, silver dollars will tell your Oscar that the tank is clear and safe, which can help reduce aggression, too. These fish prefer temperatures of around 75 to 82 degrees Fahrenheit.

5 Bichir

Photo by Jim and Tara Bliss

Bichir fish are some of the most bizarre-looking fish you will find. These fish are native to the Nile River and other areas in Africa. As bottom dwellers, these eel-shaped fish are quite long. They can breathe air, so you will sometimes see them darting up to the surface of the water for some air.

As a long fish, your Bichir should be kept in a tank that is longer than it is tall. You will want to include a tank lid, as these fish can jump. Although they are known for being peaceful, you will want to watch out for any aggression on the part of your Oscar fish. Otherwise, these long fish -which can grow up to two feet in length – are great tank mates for your Oscar cichlid.

6 Plecostomus

The Complete Plecostomus Care Guide 3

The plecostomus is a very common aquarium fish, known for its ability to eat algae. Many people purchase them to help clean their tanks. They are great Oscar tank mates as long as you keep several things in mind.

First, plecos have sharp spines on their fins which can kill your Oscars. They will sometimes try to eat your plecos, which will result in the spines being lodged in their throats. Unfortunately, this is fatal not only to the Oscar, but also to the plecos.

There are several types of plecos, but the common or sailfin plecos are probably the best options. These fish, which can grow to eighteen inches or more, aren’t likely to be munched on by your Oscars. However, you will need to keep them in exceptionally large tanks – think 100 gallons or more.

7 Green Terror Cichlid

Green Terror Cichlid
Photo by nathanreynolds1

Green terror cichlids may sound scary, but in fact, they are fantastic tank mates for your Oscar fish. They can be a bit aggressive, occasionally going head to head with your Oscar fish, but usually, green terrors won’t cause too many problems. Just make sure you select a smaller Green Terror to prevent any aggression problems.

These fish can grow up to eight inches – the smaller your Green Terror is, the better. Not all people are successful when keeping Green Terrors and Oscars together, so keep this in mind as you are readying your tank for your new arrivals – you may have to switch things around to separate the two species.

8 Jurupari Earth Eater

Satanoperca jurupari
Photo by Chris Sergeant

The Jurupari Earth Eater is unique fish. These usually grow to about ten inches in length, making them suitable in size for being housed with your Oscars. As a docile, more placid species of fish, these individuals like being in groups – an aquarium with cichlids is the perfect way to help this fish avoid loneliness. These fish are easy to feed, preferring to eat blood worms and sinking food.

9 Blue Acara

Electric Blue Acara 2
Photo by Richard Morgan

Blue acaras are about eight inches long but they can be fairly aggressive when given the opportunity. They will do a great job of standing up to your Oscars. It’s a good idea to purchase or introduce these fish only when they are adults, as it can be difficult for them to compete for food as young, small fish.

10 Chocolate Cichlids

These fish are also native to South America and are sometimes found in the same environment as Oscar fish, making them suitable tankmates. These fish easily reach over a foot in length, but they are exceptionally peaceful. As long as you don’t have an overly boisterous or aggressive Oscar cichlid, your chocolate cichlid will make a fabulous tankmate.

11 Black Banded Leporinus

Black Banded Leporinus
Photo by Craig Fildes

These non-aggressive fish are good choices for living with your cichlids because they tend to keep to themselves. Despite their docile nature, they grow quite large – often reaching a foot in length. These fish can occasionally nip at the fins of other fish, but this is not terribly common. They can also be somewhat shy, so sudden movements inside or outside of the tank may startle them.

12 Jack Dempsey Cichlid

Jack Dempsey Cichlid
Photo by John Cudworth

Jack Dempsey cichlids are quite large, often growing up to 10 inches. These fish can be extremely docile, while others tend to be more aggressive. They are good Oscar tank mates either way because they grow to about the same size – they also tend to be equal in aggressive behaviors. However, again, the success of keeping these two fish species together will depend upon the unique personalities of each individual fish. Monitor your fish carefully when they are first introduced to make sure there are no conflicts.

Which Kinds Of Fish Should Not Be Kept With Oscars?

While there are plenty of suitable fish to raise in your Oscar aquarium, there are some that have no place in this tank.

For example, you should avoid species that require immaculate water conditions. Oscars aren’t sensitive to fluctuations in the water quality – although you should always try to maintain a clean tank – but they produce a ton of waste. These fish are messy eaters and contribute a lot of nitrates to the tank.

Oscars should also not be kept with small catfish. Catfish have spines that can kill an Oscar if swallowed. While your Oscar will likely not go after a large catfish, it might view a small one as a snack. You should avoid small fish in general – Oscars are somewhat aggressive, and if you give them the chance, they will try to make a meal out of your small or slow-moving fish. As a general rule of thumb, avoid any fish that could potentially fit in your Oscar’s mouth.

Finally, you need to avoid fish that are delicate or more sensitive to aggression. Certain species, like discus fish, requires a peaceful environment and will become overly stressed if housed with Oscar fish.

Is An Oscar Tank Right For Me?

If you don’t have an Oscar fish yet but are ready to introduce some to your tank, just keep in mind the guidelines we told you about above. While an Oscar fish can do just fine on its own, it can be quite fun to have a full aquarium that is brimming with aquatic life.

These fish are excellent pets! While they may not be suitable for everyone, they are fish that should be considered by every aquarium hobbyist at one point or another.

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