I have 2 clowns and 2 Chromies + couple other fish, the larger chromies usually only gets a little bit aggressive before feeding them after its ok. Ive had the clowns and chromies to since around the sametime and they get along. I do notice the bigger one sometimes nips at a clown or the smaller chromis. Not sure whats going on tho. I really wont want to get rid of it since ive had them as my first reef fish so theyve grown onto me