Not to derail the thread, but TTM is really simple. I suggest it for all your fish and tangs!
Get two containers of water. For tangs I use large rubbermaid containers (with some rope around them so they don't sag out too much when full).
You keep the fish in one tank for 72 hours, on the third day move them to the other tank, then back and forth for at least four transfers. This interrupts the Ich lifecycle and by the end you've interrupted it enough that you don't have any more ich parasite.