Convict cichlids are one of the most aggressive small cichlids in the hobby, and finding compatible tank mates requires careful planning around their temperament, tank size, and breeding status. The short answer: you need fish that are either tough enough to hold their own, fast enough to stay out of trouble, or large enough that a convict won’t bother picking a fight.
Why Convicts Are Hard to Pair
Convict cichlids punch well above their weight class. Despite topping out around 4 to 5 inches, they’ve been documented bullying piranhas and driving larger fish into corners. Their aggression escalates dramatically during breeding, when a bonded pair will defend their eggs and fry against anything that moves. If you have a male and female together, expect them to spawn frequently, and expect that spawning to turn the rest of the tank into a war zone.
This means your stocking strategy depends heavily on one question: do you have a breeding pair, or a single convict? A lone convict is far more manageable. A breeding pair in anything smaller than a very large tank may need to be housed alone when they spawn, so having a spare tank ready is a smart move.
Tank Size Sets the Rules
The minimum for keeping convicts with other fish is around 55 gallons, and even that limits your options. Experienced keepers have successfully mixed convicts with large Central Americans like jaguar cichlids and midas cichlids, but only in tanks of 240 gallons or more. In smaller setups, the convicts simply dominate the available territory and leave nowhere for tank mates to retreat.
Convicts thrive in water with a pH of 7.0 to 8.0, moderate to hard water (9 to 20 dH), and temperatures between 20 and 36°C (68 to 97°F), though most keepers aim for the 75 to 82°F range. Any tank mate you choose needs to share these parameters comfortably.
Other Cichlids That Can Work
The most reliable cichlid tank mates are species that can match a convict’s aggression without being so different in size that one dominates the other. Jack Dempseys are a classic pairing. They grow larger than convicts (up to 10 inches) and have enough backbone to stand their ground. Port acaras and jewel cichlids (jewelfish) are also commonly kept alongside convicts with reasonable success, as both species are assertive enough to defend their own space.
Salvini cichlids are another solid option. They’re predatory toward small fish but otherwise fairly easygoing with tank mates close to their size. The Honduran red point, a close relative of the convict, is smaller and more colorful but less aggressive, which makes it a workable companion in tanks with enough room and sight breaks.
The Firemouth Problem
Firemouths are frequently recommended as convict tank mates, but the track record is poor. Firemouths bluff aggression by flaring their gill plates, but they don’t actually fight the way convicts do. Almost every time the two are combined, the convicts become bullies and the firemouths take damage. Even in a 240-gallon setup with much larger cichlids present, firemouths have been bullied so badly they needed to be rehomed. If you’re set on firemouths, keep them in a separate tank.
Fast Schooling Fish as Dither Fish
Dither fish are fast, active schooling species that occupy the middle and upper water column. They serve two purposes: they add movement and color to the tank, and their presence in open water can actually reduce aggression by making territorial fish feel less threatened. A convict that sees active fish swimming freely overhead tends to be calmer than one in an otherwise empty tank.
Giant danios are a popular choice. They’re fast, hardy, and large enough (up to 4 inches) that they won’t be swallowed. Silver dollars are widely considered the best dither fish for cichlid tanks thanks to their speed, size (up to 6 inches), and tight schooling behavior, though they really need a 6-foot tank to have enough swimming room. Keep them in groups of at least three.
Filament barbs are a less common but excellent pick. They’re bright, active, and school tightly. White sailfin mollies have also been used successfully, as they’re hardy, breed readily (replacing any losses), and tolerate the hard, alkaline water convicts prefer. Rummy-nose tetras can work if the tank is large enough, since they’re very fast swimmers, but their small size makes them riskier in tight quarters.
Bottom Dwellers and Algae Eaters
Plecos are the go-to bottom dweller for convict tanks. A common pleco or bristlenose pleco has tough, armored skin that convicts can’t easily damage, and they tend to stay out of a cichlid’s territory by hiding during the day and foraging at night. Bristlenose plecos are the better fit for most tanks since they stay around 5 inches rather than growing to over a foot.
Avoid small, fragile algae eaters. Otocinclus catfish are too tiny and delicate. They’ll be harassed or eaten almost immediately. Similarly, small corydoras catfish are poor choices because they occupy the same bottom territory convicts defend and can’t escape aggression quickly enough.
Fish to Avoid Entirely
Standard community fish are off the table. Tetras (except in very large tanks with cover), guppies, platies, and other small, slow-moving species will be killed or eaten. Anything under 2 inches is essentially live food in a convict tank.
African cichlids are also a poor match despite their similar toughness. They come from entirely different habitats with different social structures, and mixing Central American cichlids with African species typically creates constant, unpredictable conflict. Angelfish and discus are too slow, too fragile, and too peaceful to survive alongside convicts.
Long-finned varieties of any species are especially vulnerable. Convicts are fin-nippers when agitated, and flowing fins make an irresistible target.
Setting Up the Tank for Success
Even with the right species, tank layout matters enormously. Convicts need clear territorial boundaries, which means lots of rocks, driftwood, caves, and visual barriers that break lines of sight. When one fish can’t constantly see another, aggression drops significantly. Create distinct zones in the tank: a cave or rock pile at one end for the convict, open swimming space in the middle for dither fish, and a separate hiding area at the opposite end for any other cichlids or plecos.
Overstocking slightly (within the limits of your filtration) can also spread aggression across more targets so no single fish takes the brunt of it. This is a common strategy in cichlid tanks, but it only works if you have strong filtration and stay on top of water changes. Adding all tank mates at the same time, rather than introducing new fish into an established convict’s territory, gives everyone a more equal start.
If your convicts start breeding and aggression spikes beyond what your tank mates can handle, moving the breeding pair to a separate tank is the safest solution. Having a 20-gallon breeder tank on standby is practically a requirement for anyone keeping convict pairs in a community setup.