The answer depends entirely on which cichlids you’re keeping. Cichlids are one of the largest fish families in the world, spanning from the hard, alkaline waters of Africa’s Rift Lakes to the soft, acidic rivers of South America. A tank mate that thrives with Malawi mbuna would be miserable with discus, and vice versa. The key is matching temperament, size, and water chemistry.
African Cichlid Tank Mates
African cichlids from Lakes Malawi, Tanganyika, and Victoria need hard, alkaline water with a pH between 7.4 and 9.0 and a general hardness of 160 to 320 ppm. That chemistry immediately rules out most tropical community fish, which prefer softer, more neutral water. Your companion fish need to tolerate those conditions and handle the aggression that comes with keeping Africans.
Synodontis catfish are the gold standard bottom dweller for African cichlid tanks. Species like the petricola and multipunctatus come from the same Rift Lakes and naturally share the same water. Other Synodontis species from different regions can be acclimated to the higher pH without trouble. They stay near the bottom, scavenge leftover food, and generally get left alone.
Bristlenose plecos and common plecos also adapt well to African cichlid water, making them reliable algae eaters for these setups. Avoid fancy pleco varieties, though. Most require acidic water and won’t adjust to the high pH. Also skip long-finned pleco varieties if you’re keeping mbuna, which tend to nip at trailing fins.
Corydoras catfish are a common suggestion that doesn’t hold up in practice. They’re peaceful and generally ignored by cichlids, but they need much lower pH, hardness, and alkalinity than Rift Lake species. The water chemistry mismatch makes them a poor long-term choice.
Dither Fish for African Cichlids
Fast-moving schooling fish serve as “dither fish,” a term for species whose constant activity in open water helps diffuse aggression. When cichlids see smaller fish swimming boldly in the open, it signals safety and reduces territorial fixation. Effective choices include giant danios, zebra danios, Congo tetras, Buenos Aires tetras, tiger barbs, and rosy barbs. All of these are quick enough to avoid most aggression, and barbs in particular are tough enough to hold their own. Keep dither fish in groups of six or more so they school naturally and don’t become isolated targets.
South American Cichlid Tank Mates
South American cichlids get an unfair reputation. Many aquarists picture oscars tearing up plants or green terrors leaving tank mates finless, but there’s an entire category of peaceful South American cichlids that do well in planted community setups.
Severums, angelfish, and festivums are all relatively docile, laterally compressed cichlids that coexist well as mated pairs or in groups of six or more. Earth eaters (genera Geophagus, Gymnogeophagus, and Satanoperca) are another beautiful group suited to community life. They spend most of their time sifting through substrate and rarely bother other fish. Discus can work but tend to be too shy and sensitive for a busy community, doing better in species-only setups or with very calm companions.
For schooling fish in these tanks, most medium-sized tetras work well. Rummy-nose tetras, lemon tetras, and cardinal tetras all occupy the middle and upper water column, staying out of the cichlids’ preferred zones. Pencilfish and hatchetfish fill the same role. Corydoras catfish are excellent bottom dwellers here, since South American water parameters match their natural habitat perfectly.
Dwarf Cichlid Communities
Dwarf cichlids like Apistogramma species open up the widest range of tank mate options because of their small size and relatively mild temperament. Ember tetras and Loreto tetras are particularly good matches, tolerating the same temperature range of 70 to 82°F. Neon tetras work too, though they prefer slightly cooler water (70 to 77°F), making them better suited for species like Apistogramma borellii that also do well at the cooler end.
The trick with dwarf cichlid communities is choosing tank mates that stay in the middle and upper portions of the tank. Apistogrammas are bottom-oriented fish that claim small territories around caves and leaf litter. Tetras, rasboras, and pencilfish naturally swim higher in the water column, so they rarely provoke territorial behavior. Small corydoras species make good bottom companions since they’re social, non-threatening, and constantly on the move rather than holding territory.
Fish to Avoid Mixing
The biggest compatibility mistake is mixing fish from different water chemistries. African Rift Lake cichlids and South American cichlids should never share a tank. One group needs a pH above 7.5 with hard water, while the other thrives in soft, acidic conditions around 6.0 to 7.0. No compromise setting keeps both healthy long term.
Slow-moving, long-finned fish like bettas, fancy guppies, and fancy goldfish are poor choices with almost any cichlid. Even mild cichlids will nip at flowing fins, and the stress alone shortens the life of delicate species. Very small fish like endlers or microrasboras become live food for anything but the smallest dwarf cichlids.
What About Shrimp and Snails?
Shrimp are not viable tank mates for cichlids of any size. Even smaller cichlids will hunt and eat ornamental shrimp, and no amount of hiding spots changes the outcome over time. Snails have slightly better odds. Malaysian trumpet snails reproduce fast enough to stay ahead of predation in many tanks, and their hard shells offer some protection. Nerite snails and mystery snails can survive with smaller, more peaceful cichlids, but in tanks with larger or more aggressive species, snails become a supplemental food source rather than a permanent resident.
Tank Size and Setup Tips
A useful sizing guideline is 10 inches of tank length for every inch of your largest fish. A 6-inch severum, for example, needs a tank at least 60 inches long. Ignore the old “one inch of fish per gallon” rule, which dramatically underestimates space needs for active, territorial species like cichlids. For most mixed communities, a 55-gallon tank is a realistic minimum, and 75 gallons or larger gives you much more flexibility.
Breaking up sight lines is one of the most effective ways to reduce aggression in any cichlid tank. Rocks, driftwood, and dense plantings create visual barriers so that territorial fish can’t see each other constantly. In African cichlid setups, tall rock structures with gaps and passages serve this purpose. In South American setups, driftwood, floating plants, and broad-leafed stem plants do the same job while also mimicking natural habitat.
When adding new fish, introduce the less aggressive species first and let them establish themselves before adding cichlids. If you’re adding new cichlids to an existing group, rearranging the hardscape before introduction disrupts established territories and puts everyone on equal footing. Adding multiple new fish at once also helps distribute aggression so no single newcomer becomes a target.