I have heard that butterfly fish are difficult too. That said, I have had a copperbanded butterfly fish for about a year and a half that is one of my favorite fish. Mine is very friendly and always active. Very unique swimmers while picking at live rock. I think the key to success is getting them eat to eat frozen foods such as a mysis shrimp one they purge your tank of all worms and nuisance anemones (which they will do quickly). Mine adapted quickly.
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