I have a 72g with 2 clowns, 2 chromis, a sailfin tang, coral beauty and a watchman goby along with some hermits, snails and a blood shrimp. The female clown has had what appears to be ich for a few weeks now going back and forth from bad to ok. Every time I'm about to set up a qt it looks better but it's not going away. The male also has had a couple spots but not as bad and both have been eating. I haven't seen any signs of it on the other fish. So I also have a 29g that I left set up with 2 damsels when I upgraded because they were a nuisance. I'm wondering if I should move everyone to that tank and use it as my qt to treat with copper. I don't know if that will be too crowded though. I'm tired of seeing this ich and don't want to deal with it anymore. Any suggestions I can get would be great.