I have a big yellow tang that I tried to introduce to my big tank. My lunare wrasse bit his eye out first thing. I moved him to a 30g tank and over the last 30 days or so I can tell that his health has slowly declined. He still eats good and all, but I think one-eyed fish have a hard time competing for food. That being said, I also have a singapore angel that has one eye (Queen angel established its' dominance) and he does fine. He manages to get food between all the other fish. Really its' a gamble. My singapore was already in the tank, but the yellow was a new inductee. I don't think I'd try it.