I was told this was a hard fish to aclimate and now I believe it. Didn't really help that I already had a coral beauty of the same size in my 4'x2'x2' tank. The flame angel arrived great and healthy. Once added it would chase/ intimidate the coral beauty at every chance it got. It would only pick at rocks and completely ignore mysis, brine, flakes, pellets, and the nori for my 2 tangs. The fighting with the CB continued for over a month until both got tired and the CB stopped eating and went to hiding. The CB is still not eating even after the flame Angel passed 2 days ago, and it was eating plenty before. I was able to catch the flame 3 days ago, as it was very weak and went into hiding and looked like it was dying, and put it in my sump hoping the isolation would help. Next day it was dead. Sad because it was a very nice fish. Did not get lucky with the fish since it didnt eat for over a month and never got along with my Coral beauty even with 10 other fish in the tank. Even tried the mirror trick a few days on and off and nothing. My first fish of about 4 from candy corals that have died/ had problems with but will keep trusting them as I know in this hobby sometimes you just get unlucky even though you appear to do everything right. Thanks!