I can't add anything even remotely similar to a tang anymore they just stress it out till it dies. I have a 300g with a yellow, kole, unicorn. sailfin and doctor. They were all added at once and the doctor is the leader they will chase anything around till it stresses out and dies. Lost a powder blue, coral beauty and pakistan butterfly and won't risk the death of anymore fish. Added a tricolor wrasse and they totally ignore him. All those fish were added at once after the tangs.