The main — and probably the most fascinating--trait of all cichlids is the fact that they will often breed right before our eyes — and after that there will be interesting brood care, too.
Observing cichlid “family” care can be one of the most rewarding parts of keeping cichlids. Cichlids can have incredibly strong parenting instincts. Some breeders have even seen discus pairs that had lost their fry and took care of live Daphnia, mistaking it for their young.
Monogomy. For one thing, cichlids can form strong monogamous relationships (for instance, Neolamprologus brichardi, Thorichthys meeki, Archocentrus nigrofasciatus and Mikrogeophagus ramirezi). When a mated pair of a few years' standing is separated, the fish will become listless; they can also fall sick and probably will never mate with another partner.
Courtship. The male's courtship dance of some species is quite spectacular, and the same can be said about other actions calculated to draw the female’s attention. Among the Malawi mouthbrooders of the Utaka group, the males build magnificent sand mounds just to impress and attract a partner.
Nesting. Some South American eartheaters, for instance Retroculus, build "nests" out of rough stones, in which spawning then takes place. Interestingly, they need to transport the stones over considerable distances, for they are usually not to be found in the area where reproduction takes place.
Polyandry. Some species of African cichlids practice a strategy called polyandry, where the biggest, most dominant female lays eggs in the nests of a number of male partners. The males take care of the young, while the female protects the territory from aggressors.
There are also cichlids that need empty shells for procreation. Others dig tunnels in clay substrate and breed inside them. Yet others simply deposit their eggs on hard ground. The abundance of interesting breeding strategies is downright impressive, and it would be impossible to mention all of them. Much of cichlid breeding behavior is still a secret to ichthyologists, which just makes them more intriguing.
Some helpful URLs
http://www.cichlidae.com/articles/default.php
http://www.cichlid-forum.com/articles/breeding_list.php
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