I agree that a varied diet is best. However, let not forget that cichla are primarily piscivores, which means fish eater. Believe it or not, a cichla can get practically all the nutrition it needs from just eating fish. Common sense would dictate that cichla in the wild eat any fish they can catch, healthy, sick, or otherwise. Digestive acids in the gut rapidly break down flesh, gut, and bone. We all know a feeder is consumed by cichla as soon as it hits the water. So, unless a diseased feeder is allowed to swim in the cichla tank for an extended period of time, the transmission of disease from a feeder to cichla would have to be very, very small. I've heard the "sick feeder" theory for years, but I've never seen proof of it. I did read on a forum about a guy once who swore feeders gave his fish ick, but he kept his tank of juvies at 75 degrees. That only proves that he kept them at such a cool temp., that the feeders most likely had nothing to do with it. Having said all this, fish species fed to cichla should be varied, and goldfish, rosies, or other members of the carp family make poor feeders for a variety of reasons. Dry foods such as Hikari Massivore make an excellent substitute. From my experience, small fish fed a variety of live foods grow faster and stronger than fish raised on prepared foods. When the fish gets some size on it, then prepared make an excellent substitute.