I have also read about a Steroid based pellet food that is being used in grow-out facilitys.
If you go to your local PetSmart and see some amazing Peacock cichlids with BRIGHT coloration, this could be one of them. Most people know they don't show that kind of coloration until they are adults. However, some fish when fed these steroid pumped foods, they will show adult coloration far before they normally would.
I don't know how true this is.. I have also heard about a chemical you add to the water, but I don't know about that either..