Not trying to start a war, but I read that cleaner shrimp and wrasses help w/ ick, but can't rid a fish/tank of the parasite because they only can eat the parasites on the surface of the infected fish. Somebody who "sounded smart" wrote on another website that ich buries itself into the flesh of the infected fish, and therefore the cleaner shrimp/wrasses can't get all of them. is this right?
The only foolproof way I've seen to rid your entire display tank of ich is to capture and remove all of your fish to a hospital tank, and let your display tank sit fallow for over a month, thereby starving out the ich parasites still in the display. assuming you successfully treat all your fish in the hospital tank, you won't be reintroducing any ich to your display when you dump your fish back in.