Nonsense..... not good for cichlids..... Plenty of dwarf cichlids to choose from and many with wonderful personalities. Most can be placed in a communtiy of fish and everyone will be happy. Rams and apistos seem to be the two most common.
Convicts could work as well but if you have a breeding pair, then only the pair in the tank as when they spawn (and they will over and over and over...) they become so protective of the eggs that they will def kill everything else in a 30G. Another member had a 350G tank with a pair of convicts in it. That pair dominted the tank filled with a GT, an Oscar, and several other convicts. So that shows to the extent of how protective they will be. But you could have just one and a few other community type fish, something durable and stout enough to hold its own against a cichlid, a pleco and some cats for instance.