Was the aggression only towards new tangs or any new fish that you added?
Nope... He killed a Foxface, Mandarin and something else I can't remember at the moment. I will say he still hates the lawnmower blenny to this day. Good fish, just a D!ck....
Since I added the yellows and a purple he isn't the dominant fish in the tank.
FYI, the tank is a 240. 8'x2'x2'
Still fat and Happy, just not king of the kingdom. All fish have a personality, some good, some not so good. Depends on the individual fish. When I got him, I had the mindset that Kole tangs are mellow, and thought it best to add a non aggressive fish first before the ones I knew would potentially be trouble with other tangs.. I was proven wrong with mine..
Still a really cool fish, just be warned that the generalities about certain species are not always correct.
Best of luck!