I already have a purple tang.. had him for a few months now and I have been offered a yellow tang similar size and blue tang to put into my tang. Since yellow tangs are rare I really want to put him in. I understand that they won't get along together. But adding a blue tang with the yellow tang at the same time might help? I may upgrade my tank soon but I have been offered two tangs now. Any ideas how im supposed to make this work?