What is necessary for a butterfly fish. I have tried a few and the arguia I love I just cannot keep a butterfly fish for some reason. There is nothing wrong with my water quality. Can someone help!

The only problem I see is "filstar xp3 canister" how often do you clean it? Every week at least I hope, if not....your causing problems for yourself. My lfs has 5 Koralia 8's on his 250....thats 16,000gph in just flow......so I dont think thats your problem. fish are used to massive amounts of flow in the ocean. Butterfly fish peck at corals, so add with caution. I have no idea why it would be dying though. Are you acclimating them? How long have they been at the lfs? I would ask to put it on hold for a few weeks. then come back and get it in a few weeks........then you know its healthy.

You could get rid of the canister now. Its probably doing more harm than good. Yeah, you usually run the skimmer 24/7 but it will pull some massive amounts of stuff out of your tank. :) If you have live rock in your tank.......you dont really need your canister.