Ah!! One of those guys. We call them something else but I've forgotten what. Seeing as it's a semi aggressive mbuna you should really only put it with other mbuna of the same temperament. Other Zebras, Maingano & P. Socolofi should all work. The probem is going to end up being the tank size. 30gal isn't really big enough for a mbuna tank. You could work with 45 gal but usually 55gal is considered the minimum.