Aggressive and sometimes predatory, the African cichlid does best with freshwater fish, such as Synodontis catfish, Botia loaches, Labeo sharks, suckermouth catfish and the larger tetras. Issues with cichlid compatibility often stem from aggression, which Cichlid-Forum.com attributes to the fish being too closely related or having too similar morphology, triggering an instinctive territorial response. The Malawi cichlid homepage lists the ideal ratio as being three females to one male.
African cichlids consist of literally thousands of different species, making tank compatibility a matter of trial and error and research. According to Cichlid-Forum.com, carnivorous, omnivorous and herbivorous cichlids can be kept together provided their diet meets all their nutritional needs adequately. Cichlids should all roughly be the same size as each other in order to prevent predators from eating their smaller brethren. Depending on the lake they come from, cichlids can have varying preferences for their pH levels. Keeping cichlids of separate species together may also result in hybrids with unpredictable behavior, damaging the overall harmony of a tank. Malawi Cichlid Hompeage also recommends establishing a stable routine to avoid stressing the fish unduly and to build a tank community with juveniles that are able to adapt to the presence of other fish.