Ok, i recently place all my fish in QT with copper. I'm leaving my DT fish-free for 8 weeks. This is supposed to be long enough to kill all ich in DT and on the fish. Any new fish will spend 2 weeks in QT. My question is will ich ever be a problem or will this take care of ich for good? I recently heard that ich will always be a problem no matter what i do, if stressed is presented. Is this true?