I started my tank about a month ago w/ just live sand & rocks. Waited a week or so & all my chemicals were testing good. Then started w/ 3 yellow tail damsel & 3 clown. Had them for a week or so & chemicals & water were doing great. Had a little slime, but have eliminated most. Then another week or so got a yellow tang, fire angel & some snails...same thing everything great. Then just last night I picked up a blue tang, "dorie" & came home & my fire angel was laying on the bottom gasping for air. It was breathing real fast & would try to start swimming & was able to for a second, then would fall back on it's side again. Since I bought it, it would hide most the time & not come out. I have a concern on the blue tang because it does the same thing...hides & never comes out. What should I do about my tank. I'm afraid my other fish may become sick from the fire angel.
PLEASE HELP!! 

