How Many Cichlids In A 55 Gallon Tank?

The good news is, yes, you can keep cichlids in a 55 gallon tank and by choosing the right species you will be able to have numerous colorful cichlids living happily and healthily in your aquarium.

Use this guide to give yourself 55-gallon cichlid tank ideas that suit the needs of your fish. There is plenty of specific cichlid suggestions (and number you can keep) towards the bottom of the page.

A cichild swimming in a 55 gallon tank.

Once you understand what is required to properly set up a 55 gallon African Cichlid tank you will be able to stock it with fish that will grow healthy and provide you with years of entertainment. Depending upon the species being kept, two or more cichlids will fit nicely into a 55 gallon aquarium.

Your 55 Gallon Aquarium

There are a few considerations to think about with the Cichlid tank that you are preparing…

Approx tank dimensions

Often a main consideration for choosing a certain tank size is the space available in your home (or that a spouse has allowed – are we right?).

The standard dimensions for a 55 gallon tank will be 48 1/4 x 12 3/4 x 21 inches, with the exception of a tall tank. This will often add an extra four inches of height at the expense of other dimensions.

This space should accommodate the cichlid tank but you may also need to think about the additional equipment needed. For example, the additional space needed for a canister filter.

55 gallon aquarium weight

Finally, the weight of a Cichlid tank of this size should also be considered as you set it up in your home. Water weighs in at 8.34 pounds per gallon, which would come to just over 458 pounds in a 55 gallon aquarium.

That total does not include other equipment, substrate, or your Cichlids, which would bring the total weight closer to 625 pounds, on average!

Acrylic vs. glass Cichlid tank

Your first decision will be between a 55 gallon tank made from acrylic or one made of glass. A Cichlid tank made from acrylic is lighter and more durable than a glass tank, but they scratch more easily and have a higher price.

A 55 gallon aquarium made from glass will not scratch easily and is cheaper, but they are more susceptible to breaking and will not hold water temperatures as well as an acrylic tank.

Other Cichlid Tank Considerations

The total number of Cichlids that you can keep in a 55 gallon tank can be affected by more than just the volume of water. Oxygen exchange takes place on the surface of the water as it interacts with the air.

A greater surface area can house more fish, so keep that in mind when looking at a standard landscape 55-gallon Cichlid tank when compared to a tall aquarium.

Some Cichlids grow very large and will require enough room to turn around in their tank once they reach adulthood. A 55 gallon set up is great for small as well as most medium-sized Cichlids. Larger varieties may require a Cichlid tank with a lot more room – sometimes going into the hundreds of gallons.

Something that often gets overlooked in a 55 gallon cichlid tank setup is the filtration that keeps the water column clean. More fish can be kept in a tank with adequate filtering, so it would be best to find a filter that handles biological, chemical, and mechanical filtration. It should also be able to filter the entire water column four times an hour (ratings over 220 gallons per hour are sufficient for 55 gallon Cichlid tanks).

Cichlids are territorial and enjoy spots that they can retreat to for hiding purposes. That means that you need to consider the materials, such as pots and rocks, that will be used to create space for your fish. Caves offer privacy as well as an anchor for the Cichlid’s territory but will take up tank space that can be used for more fish.

Which Cichlids Can You Keep in a 55 Gallon Tank?

Once you have set up your 55 gallon tank, it is time to stock it with your favorite fish! A rule of thumb for stocking aquariums has been to add no more than one inch of fish for each gallon of water. With their personalities and physical traits, Cichlid tanks should be stocked with no more than one inch of fish for every two gallons at minimum, or even one inch for every three gallons for a healthier environment.

This measurement should take into account the size of your Cichlids as fully grown adults and not their current size if they are younglings or juveniles. That will provide them with plenty of room as adults, reducing their stress levels which helps with their aggression and resistance to disease. Keeping in mind one inch of fish for every three gallons of water will help to negate the loss of volume due to other equipment, hiding places, and substrate in the Cichlid tank.

African Cichlid Tank Ideas

African Butterfly

African Butterfly in 55 gallon tank

If you are looking to answer “how many African cichlids in a 55 gallon tank?” with “a lot” then the African Butterfly is your fish. This dwarf variety reaches 3.15 inches as adults and has a fairly peaceful personality. Even in a tank with many decorations and hiding spots, you could keep from four to six in your Cichlid tank.

African Peacock

The African Peacock can grow between four and seven inches as adults. These fish form schools in the wild and will appreciate more open space in your Cichlid tank. Keeping two fish is ideal, but with proper filtration, you could keep up to four of these in your 55 gallon aquarium.

Buffalo Head

The Buffalo Head is smaller variety that reaches 4.5 inches maximum, you will find them also listed as Blockhead, Humphead, or Lionhead Cichlids. They are peaceful in nature when compared to many other species you could house in your Cichlid tank. Our suggestion would be to keep no more than four in your 55 gallon aquarium.


This large variety can reach over nine inches in length. Due to their size, you should keep no more than two in a highly filtered Cichlid tank (it may be even better to house them in something larger than a 55 gallon African Cichlid tank, to begin with).

Zebra Mbuna

Reaching five to six inches in length when fully grown, the highly aggressive Zebra Mbuna should not be kept in a 55 gallon aquarium with other species that are more docile. We would recommend no more than three in your Cichlid tank, with two being an ideal number.

Central American Cichlid Ideas

Convict Cichlids

With a maximum size of five inches, the convict cichlid can bully fish larger than themselves. If your Cichlid tank will include this species, avoid adding more docile cousins to prevent compatibility issues. Up to three Convicts can be housed in a 55 gallon tank easily, four if you push it.

Firemouth Cichlids

The Firemouth Cichlid grows up to six inches. This species is known for its unique (and fragile) jaw structure. Due to their weak jaw, it is best to keep them in their own Cichlid tank. A pair of Firemouth are perfect for a 55 gallon aquarium, but you could add a third with strong filtration.

South American Cichlid Ideas

German Blue Ram

The German Blue Ram is a cichlid reaching just two inches in adulthood. This dwarf variety hails from the Orinoco River Basin. They are highly territorial, however, and should be housed in pairs with plenty of space provided in your 55 gallon tank. Due to these restrictions, we suggest two pairs, or three pair if you can evenly space out their territory in the Cichlid tank.

Oscar Cichlid

The Oscar fish can grow to 14 inches when mature. For many enthusiasts, a 55 gallon aquarium is too small for their Oscar. If you decide that you want an Oscar in your Cichlid tank, we recommend that you keep only one.

Severum Cichlid

Between 8 and 10 inches in length, an adult Severum is big enough to dominate your Cichlid tank. They do have a fairly peaceful disposition, allowing them to coexist with others. You will probably not want to keep more than a pair in your 55 gallon aquarium due to their size.

Blue Acara

Blue Acara can grow up to five inches as an adult. They can be kept with a variety of fish and are considered great for beginners. You should keep no more than two pair in your Cichlid tank.

Taking Stock Of Your 55 Gallon Aquarium

A 55 gallon aquarium will make a great Cichlid tank if you take the time to set it up properly. If you are new to the hobby, keep in mind that a 55 gallon fish tank requires ample room and sturdy support. Your Cichlid tank will also require ample room to hide as well as swim.

While a lot of species may be too large for a 55 gallon aquarium, many African and Central or South American cichlids will thrive in them.

If you have experience in keeping Cichlids in a 55-gallon tank or have any questions about the topic covered here, we would love to hear from you below. Remember to keep your hobby fun for you and safe for your fish!

How Many Cichlids in a 55 Gallon Tank - CichlidGuide.com - I didn't realise it would be that many... go figure.