ow. Jared speaking even as a rank beginner in SW can I say that sounds like a rather heavy bioload? Is it possible that keeping that many fish in a 55 (particularly the tang swhich I thought needed an 80 or so just for themselves might be what contributed to an ich outbreak?
Sounds like your best bet would be to follow Greech's advice (always a wise decision in any event.
) and then maybe think about rehoming the tangs and maybe 1 or 2 other fish to reduce the crowding. Less stress will certainly help the fish recover on their own in addition to the fortification in the foods he recommends.