Once you treat a tank with copper it is virtually impossible to get the copper out and you can't put anything in the tank again that is susceptible to copper. If you plan to make it a planted tank, then I wouldn't put copper in it. If you are wanting to use copper to treat your fish and prevent ich in your new tank, I'd suggest going the hyposalinity route instead so that you can re-use the tank. If you do go with copper, make sure you don't have any live rock, sand, inverts, corals, etc. in the tank, and you'll just have to plan on using the tank for fish quarantine from there on out. If you are only thinking of using copper to get rid of the aptasia, don't use copper - aptasia x works just as well, or you could add a fish that will eat it. With your mix of fish, I think you might be able to add a bristletail filefish which are known aptasia eaters. Hope someone else chimes in on this! I wouldn't add a butterfly though, your fish are just to aggressive for a butterfly.