My mother has a 55g tank with 7 different African cichlids. They are all small, no bigger then 2 inches. i dont know breeds because it was from an assorted tank from petco. i told her she could through some roman lettuce in there to make sure that the older ones didnt hog all the food. she said that they devoured it. can they eat themselves to death or fill themselves and neglect there flake food? if they do neglect the flake food will they lose nutrition, therefor only should be fed veggies from time to time?