While they are not the meanest or most aggressive cichlid ,they think that they are!!!They are 1 of the more prettier cichlids,but once they get to a certain size (4-5 inches) it is very hard to put new tank mates into thier tank.Constant harrassment usually leads to the death of the new fish(or the Blackbelt)Best kept with larger Oscars,Dempseys,etc.They do prefer "greens"in thier diet,i used a veggie pellet made by Hikori.Best colors are between the size of 4-8 inches,once they get bigger thier colors tend to fade.All in all a nice cichlid to keep.