I have 2 QT tanks with copper, and cleaner shrimps in my display, and I know that removing all of the fish for 4-6 weeks will cure the ich, what my question was trying to ask was this, I have QT'd all of my fish with copper, I only buy my fish from a LFS that keeps all of their fish in copper, so how the ich got in my tank in the first place, I don't know, but if it got in there once, would it be waiting again when my fish get out of QT?