Among the thousand or more species of cichlid (pronounced “sick-lid”) are some of the most audacious of the freshwater aquarium fish.
This cichlid family comes mostly from Africa but also numbers about 400 species from South and Central America. The family includes the heavy-bodied Oscar with its orange-ringed black spot at the base of its tail; the blue-green spotted, big-mouthed bruiser called the Jack Dempsey; the discus, a fish with flattened flanks that looks like a plate set up on edge; and the freshwater angelfish.
While specimens of these species can grow up to 12 inches long, another group of cichlids, called dwarf cichlids, are colorful miniatures that grow only two or three inches. Physically, the most distinguishing characteristic of all the cichlids is that they have one spiny dorsal (top) fin that stands up like a stiff headdress and one soft dorsal fin.
You can see the most distinguishing behavior of these fish in their breeding habits. After most fish lay and fertilize their eggs, they leave the young to fend for themselves. Cichlids, however, take part in complex courtship and breeding behaviors. Eggs are usually laid on the bottom, and the male then stands by them, fanning them with his fins in order to increase the flow of oxygen over the eggs. When the eggs hatch, one of the adults nearly always remains to defend the young for the first weeks.
Another strategy is called mouthbrooding. After a female lays the eggs she takes them up and holds them in her mouth until they hatch.
If you are thinking of keeping cichlids, make certain you know the conditions your species requires. While many of the fish, especially the South and Central American varieties, live in freshwater jungle streams, some of the African varieties are native to saline lakes and need water that has a higher salt content. All of them need good places for shelter in the tank, ideally among plants or in caves. A nearly neutral pH is fine and the water temperature should be in the mid-70s Fahrenheit.
Cichlids can be vegetarians, meat-eaters or omnivores. All of them, however, can be fed on flake food so long as you add the occasional feeding of worms, insect, larvae or chopped raw beef heart for the carnivores such as the oscar.
Cichlids can be aggressive fish so they are not good choices for the small community tank.