So I have moved all of my fish to a HT to be copper treated for ich while I leave my tank fallow for 9-10 weeks. The problem is, it took a couple days to catch all the fish plus I let all the fish get use to the HT before I started copper. It total it has been about 7 days since the first fish went in until I just started the Cupramine. Does that mean that I now possibly have some ich in the encysted stage in my HT and, if they can last in that stage for up to 72 days, the fish can catch ich again after a 4 week copper treatment? Should I treat for 4 weeks, observe for 4 weeks, then maybe treat again the last week or 2 before they return to the DT? The HT does not have any substrate or rock, only PVC and a sponge filter.