in my 120 I have 2 tangs, a 4 inch scopas and a 4 inch something that resembles a kole but has no yellow ring around the eye and has purple lips... anyway, when I first put them int he tank together there was alot of bickering, but they get along now following each other around often. The scopas seems to let the other one find the food and then helps himself to it. As they get bigger I'll have to get a bigger tank for the scopas... oh darn