I would try to get the fish in a qt and treat with copper power. However if you treat your tank you can have corals again. You will need to do some massive water changes and run cuprasorb for a few months to absorb any leaching. Here’s a pic of my tank. I had .17 ppm copper in august from a bad prob holder magnet and some how my ro/di unit got copper bombed. The inside of the ro membrane housing was teal. Currently my copper tests at .04 on my Hanna. However my ATI test two months ago said undetectable. After my magnet blew up I will always run cuprasorb as a precaution. It saved my corals.