I got some of rapps' "rio guatape" Umbee which I believe are gorrilus blues a while back. I have four of them (3.5" to 5.5") in a 135 with a 6" Rio mag that I just recently added. I did have them with some midevil growouts until they passed the umbees in size and began increasing aggression and beating the Umbee off the food. That's when I pulled the midevils and added the Rio mag. My question is should I leave the 5 Umbee alone in the tank or add more dithers? Maybe some convicts or something else that isn't likely to be too aggressive? My ultimate goal is to get a pair out of the group. Would prefer for the gorillus to pair off but if the Rio mag pairs with one of them I would be happy too. I do think that's how they get the ultimate blues. Correct me if I'm wrong.