Firemouth Cichlids are very pretty fish, and they brighten up any tank quite nicely. However, Cichlid species are known for being one of the most aggressive species of fish, which makes it difficult to try and find other fish that will coexist in the tank with them.
So what should you look for? What kinds of fish are compatible with cichlids? Here’s a list of 15 fish that can peacefully coexist with a Firemouth Cichlid:
1. Brittlenose Plecos

Firemouth Cichlids are very territorial over their space, so if you want to build a tank with a variety of fish, it’s better to buy fish that will inhabit different areas of the tank than the Firemouth Cichlid. Brittlenose Plecos inhabit the bottom of a fish tank and don’t move around a whole lot during the day.
Brittlenose Plecos mind their own business and hardly paying attention to fish that swim above them. They are generally pretty peaceful, which means that they are not likely to provoke the Firemouth Cichlid. If the Firemouth Cichlid does try and go after them, they have hard armored scales that make it easier for them to resist nips or suspected attacks.
The Brittlenose Pleco is known for the bristles around its nose and the spotted coloration that adds uniqueness to whatever tank it may be in. They typically grow three to five inches and have an average lifespan of five years.
2. Swordtail Fish

Swordtail fish are very similar to Firemouth Cichlids in care and size, so they make a good tank mate. Both Firemouth Cichlids and Swordtail fish are from Southern Mexico, and they both thrive in temperatures between 72-78 degrees Fahrenheit. The similarity here makes it easy for these fish to live in a tank together.
The Firemouth Cichlid gets along better with fish of its own size, which works out well for the Swordtail fish, as long as an adult is put in the tank and not a baby. Furthermore, the Swordtail fish has a pretty peaceful temperament and are unlikely to provoke or bother the Firemouth.
Swordtail fish grow to about 6 and a half inches, and they live an average of three to five years.
3. Rosy Barb

Rosy Barbs are a good fish to put in a tank with Firemouth Cichlids. Rosy Barbs have been known to nip fins, which can be troublesome for fish with trailing fins, like Bettas. However, Firemouth Cichlids will not tolerate fin nips and will fight back against the rosy barb.
The defense mechanisms of both the Firemouth Cichlids and the Rosy Barbs help them to live together, because they will typically learn to leave each other alone, and they can both defend themselves if attacked.
Rosy Barbs grow up to six inches and can live for five years in captivity.
4. Rainbow Fish

Rainbowfish are shy and not very aggressive or confrontational. This personality of theirs makes it easy to put them in a tank with Firemouth Cichlids because they will not provoke them or even invade their territory. Rainbowfish will mind their business and stay in their own area, which is ideal for the Firemouth Cichlids, who are very territorial.
Rainbowfish also are excellent hiders, and if they feel threatened at all, they will find a hiding spot and stay there until they feel safe. Therefore, even if the Firemouths do get angry at them, the Rainbowfish can escape their attacks.
Rainbowfish are named for their variety of colors. Boseman Rainbowfish average around 4.5″ in length and live five to eight years.
5. Rummy Nose Tetra

Tetras work very well with Firemouth Cichlids because they are school fish. Schooling fish tend to stick together with one another and they have a peaceful temperament. Due to this peaceful temperament, they won’t provoke the other fish, but they will fight back if they are attacked.
Rummy Nose Tetras are also very good at hiding, so if by chance the Firemouth becomes aggravated, they can easily escape its wrath by hiding, as long as the tank has lots of high-quality hiding spots.
These fish are generally chosen for tanks because they are very attractive, with a variety of colors and patterns. They are easy to care for and are generally bought in groups. They average only about two inches and live five to six years.
6. Glowlight Tetra

Glowlight Tetras are very similar to Rummy nose and will not generally provoke a Firemouth Cichlid. They are schooling fish, so they will fight back if they need to.
When housing a Glowlight Tetra and a Firemouth Cichlid, you have to balance the pH of the tank to be neutral, or 7.
Glowlight Tetras have vibrant colors and brighten up any tank. They should be bought in groups of at least six. They are generally pretty small, averaging only one and a half inches. Glowlight Tetras have an average lifespan of two to five years.
7. Convict Cichlid

These Cichlids are native to the same area that Firemouth Cichlids are, which means that the species will peacefully coexist, as long as the tank is large enough to accompany both of them.
When housing both Cichlids, the tank should be large, (over 30 gallons at the very least) so each Cichlid feels like they have their own space. There should also be lots of rocks and driftwood for the fish to dart between and so that they aren’t always in the view of the other one.
Convict Cichlids typically have stripes, and they grow up to 6 inches long. The average lifespan of a Convict Cichlid is eight years.
8. Pictus Catfish
Pictus Catfish are bottom dwellers so they operate on a different level of the tank than the Firemouth Cichlids. This means that there is little chance of territorial issues between the two fish. These catfish are also non-territorial and have a generally peaceful temperament.
When housing a Pictus Catfish, there has to be enough room for them to swim around, so the dimensions of the tank should be fairly large. Furthermore, you should not try and breed Firemouth Cichlids in the same tank as the Pictus Catfish, because the catfish will eat the small fry of the Firemouth.
Pictus Catfish are known for their dotted appearance. They grow up to six inches long and can live for over eight years.
9. Corydoras

Corydoras are a good tank mate for almost any fish. They have high adaptability and can adjust to a huge range of water parameters. This makes it easy to place them into a wide variety of tank sizes. They are also one of the most commonly available fish, so they are very easy to get ahold of.
Corydoras are also schooling fish and when in groups, they can successfully handle the chase of an angry Firemouth Cichlid. Their large size makes it easier for them to live alongside Firemouth Cichlids.
10. Clown Loach

Clown Loaches are large enough to not get eaten by the Firemouth Cichlids, but they are peaceful enough to not provoke them. Clown loaches are bottom dwellers in a tank, and therefore will encounter no territorial issues within the tank.
Not only are they peaceful bottom dwellers, but they also are excellent at camouflage. They blend in with the rocks and decorations at the bottom of the tank, which makes it difficult for Firemouths to be provoked by them, or even notice that they are there.
Clown Loaches are generally orange with black stripes. They can grow up to 20 centimeters and live 10 years on average.
11. Pearl Gourami

Pearl Gourami are relatively the same size as Firemouth Cichlids and therefore can get along okay with them. They have a very peaceful temperament, and will not provoke or cause issues with the Firemouth Cichlid. Pearl Gouramis generally dwell near the top of the tank and are likely to not invade the territory of the Firemouth Cichlid.
The Pearl Gourami is a very attractive fish, with pastel colors and spots all over. This fish can grow four to five inches long and lives for about 5 years.
12. Salvini Cichlids

Salvini Cichlids are similar enough to dwell in a tank without encountering a ton of issues. The Salvini is relatively small for its family and is also less aggressive than some of its cousins in the cichlid family.
Cichlids are very territorial, so in order to prevent issues in the tank between the Firemouth and the Salvini, it is important to provide a large tank, so that the fish can have their own territory that doesn’t interfere with one another.
Salvini Cichlids grow up to 8 inches long and live 10-13 years. They vary in color and typically have black spots across their scales.
13. Oscars

Oscar Fish is large enough that Firemouth Cichlids won’t try to bother them or attack them, and therefore these two can dwell in a tank without any major issues. Firemouth Cichlids are likely to flee from the Oscar fish if they attack, but they can also stand up to them and fight back if it comes to that.
The Oscar Fish is actually from the Cichlid family, so there is a similarity between the two fish and tank conditions-such as temperature and decorations of the tank.
Oscars are generally chosen for a tank because of their fun colors, and because they are pretty hardy and can withstand a lot. They are also fairly easy to care for. Oscar fish are pretty large, growing up to 14 inches and they live anywhere between 10 -20 years.
14. Severum

The Severum Fish is another Cichlid breed that can dwell in a tank with a Firemouth Cichlid. The Severum grows larger than the average Firemouth Cichlid, so the Firemouth will wisely not try and attack.
As long as both of these fish feel like they have plenty of space and rocky decorations, they will have no problem getting along. If they are in a small tank or do not have a lot of decorations or hiding spaces, they will become more aggressive toward one another.
Severum fish come in a variety of colors. They average around 8 inches and live about 10 years.
15. Rift Lake Cichlids

Rift Lake Cichlids are similar to their Firemouth cousins. They prefer similar temperatures and rocky hiding places. This makes it easy to add them to a tank without having to change anything about the habitat.
Rift Lake Cichlids, especially the electric yellow lab, have peaceful temperaments and beautiful colors. They add variety and color to a tank and aren’t too difficult to care for.
However, cichlids, in general, can become aggressive, so be prepared to watch the tank and possibly remove one breed if the cichlids are not compatible with one another.
Rift Lake Cichlids come in a large variety of colors and shapes. They can vary in size anywhere from four inches to 12 inches. These fish generally live around 10 years.
Things to Consider when Building up a Firemout Cichlid Tank
Although all of these species listed above can share a tank with the Firemouth Cichlid, many of them are not compatible with one another. If you are planning on putting several different kinds of fish in a tank, it is important to do research and check the compatibility of the fish with all of the other fish in a tank.
If you are planning on breeding fish, it may be necessary to move them to another tank so that their eggs don’t get eaten. This can be said for Firemouth Cichlids, but also for any tank mates of Firemouth Cichlids because they are known to eat eggs or small fish.
Firemouth Cichlids are very territorial, so it is important to provide the necessary space and to chose fish who dwell in different parts of the tank than them. The tank should also have a variety of hiding spots for the other fish to utilize in case the Firemouth Cichlid does become aggravated or angry.
It is noteworthy that, although these fish are generally compatible, the specific compatibility depends on the individual fish and circumstances. It may be necessary to monitor the tank and/or remove fish if problems arise.