Me and my fiance bought 4 angel fish today we put them in the tank and went to work when we got home we couldn't find one of them we saw the other 3 one looks like its tail fin night be clamped (treating with Mela fix) they're body is about the size of a nickel (that's without the fins). My filter is a marine land 350 I knew it was powerful but is it going to kill the rest of my angel fish????? I don't even understand how this could happen! Please help! I don't know what to do at this point!! Us there something I can use to cover the intake???