adding more fish

[atrain]

I currently have a kole tang, yellow tang, percula pair, 6 line wrasse, 2 lytretail anthias, 6 line wrasse, blue throat trigger in a 180 gallon. I would like to add more however, everytime I do, they get beat up and die. The tank is established and I am unable to get the current fish out. The kole tang is the main problem, the trigger and yellow tang will join in occasionally. I was thinking of adding 8 chromis, possibly an angel or another wrasse. Would it help if I added them all at the same time? or am I just looking for trouble without removing the kole tang?
Any help is appreciated.

 

[Dkuhlmann]

Put an extra large Emperor Angel in there and see if they pick on him :lmao:

What about some of the larger wrasses?

 

[horseplay]

Get a fish trap. tangs are not difficult to trap. I would remove the aggressive fish now. You still have a lot of room in the tank.