I once had a dottyback with my two skunk clowns, it lasted about a month in my tank before it became way to aggressive, it's now living in my roomies tank and still picks on his other fish which include a tomato clown, a damsel, and a kole tang. Dottybacks like a lot of other fish can be mellow or aggressive, depends on the fish and it's enviroment.
Sorry Jim, I know that probably doesn't help much but these type of fish are basically a 50/50
