I normally don't disagree with reefers with more experience than me but, I converted a FW tank that I know for a fact had copper based treatments used in it (because I put it in) to a SW tank after a thorough cleaning and had no problems. I first set it up as a QT tank, but after about a year of it sitting with nothing ever being put in it I started stocking it. Just some fish, snails, a couple
feather dusters, and a shrimp. After the first fish went in, I put a couple turbo snails in (as a test) and they were as happy as a pig in slop. I then added the live rock and the rest of the inverts. I didn't loose anything until I had a temperature enduced crash (97 deg.). The inverts were fine in the tank. I eventually took it down and two weeks ago my nephew set it up at his house. It already has some liverock from my reef in it and will be getting more. I think it will be a FOWLR. But if the kid gets the reef bug, I have no doubt it will be fine. I am not saying that this situation is the same in all cases but in my case I was able to reuse a copper treated tank. BTW it was a 29gal glass tank.
Eric...
