Almost everything I have is either in pairs (Mated) or a more than 2 so they can school. Successfully keeping 3 yellow tangs with no aggression. I credit the tang decoys and abundant food as the key of keeping multiple yellow tangs in the same tank.
Here is a before and after...almost beat these rotten dinos. No more fluconazole for me. I knew better than to use a bottle of magic. I'll be using an alage scrubber in the future. The nice part is, they can before dino scrbbers if it all shifts that way again. I threw everything at them, and nothing seemed to help besides seeding the sump with hair algae and blasting it with light as well as keep no3 and po4 elevated.