I bought a yellow tang and a blue tang from somebody's tank two days ago, and saw ick on the blue tang today. My tank has been ick free for a long time now, and the two tangs looked perfectly healthy when I bought them. I know transportation can stress the fish, especially the blue tang. But is this normal? What can I do now? I am afraid that the Ick might spread to other healthy fish in the tank, and I can not take out the blue tang because of the rocks. Should I go get a cleaner shrimp? Anything else I can do? Thanks.