Two years ago before I knew better... visiting the LFS after setting up my 125 gallon tank (72x18x24), they had an adult yellow tang that was severely beat up from being attacked by damsels. My wife had to try and save it so we stupidly added the yellow tang, a younger sailfin and a juvenile yellow belly regal tang that thought he was a chromis for weeks and schooled with them. Suprisingly and luckily, they all get along very well. The yellow tang has colored up very well but has not regained all of it's fins but is the boss of the tank. The sailfin follows the yellow around and the yellow belly just hides in "his rock" until the food hits the water which he has done since he figured out he could fit in it. Needless to say it has been two years and the yellow belly is now about the same size as my flame angel. The other fish consist of 3 clowns, 2 chromis, 2 pajama cardinals, 1 bicolor blenny and an engineer goby that just won't die. I know these guys need or will need a bigger tank, the question is how much bigger? And when? I had planned on doing a 180 but am curious if that is big enough. Would I be better off finding one or two other homes? I only post this in the fish section because it's more about the well being of them than the tank size because if something happened to my wife's yellow tang, I would probably go to a much smaller tank since they are the only reason it is still up and running.