I have a long story but I think you need to hear it in order to hepl me SORRY!!! About 4 years ago I had to treat my fish for ich. I let the main go fallow and treated the fish with copper in another tank. When I reintroduced my fish back to the main tank. I lost all my inverts. I thought maybe an ammonia spike but nope. I came to the conclusion that some of the equitment ( IE the filter ) I used in the qt must have had trace amounts of copper in it. I had an hob
filter on the main before I treated my fish and I used it to help cycle the qt. I changed out all the media and the bio wheel before I put it back on the main tank but I guess lesson learned. ANYWAY, I have waited 4 years. I resently had to move my tank so all the sand was replaced and I did a 90% water change. I used one of those poly-filters that take out copper and to my surpize it didn't change color. I was told that the filter changes to blue if copper is present. I am hoping that my copper issues are over. I love inverts and some of the copper sensitive fishes. I am wanting to get a coral beauty but I don't want get it and chance killing it. Thanks so much!!!!!