Wholeheartedly agreed on the NTT dats.I have pretty much given up on them after my last one checked out on me after coming along so nicely for quite a while.It wasn't the first one to do so either.I would suggest: the more you get, the less they fight. NTTs also just up and die for no apparent reason, IME.
However, I have personally had one that would bash the sides of other fish and kill them. Guess it would pop the swim bladder. That was an NGT though. Meanest dats, again just in my experience. Good news, I’ve had 2” with 6”, 8”, etc.. and no problems. Get more you’ll be better off.