I don't understand it. I keep puting new fish in my tank and they do great and then dissapear. The original fish are still in the tank but when ever I buy something new it is fine for a while and then disapears. I do quarantine them for 3-4 weeks before I put them in the main display tank. My recent fish were 2 fire gobies and 1 sole tang. Does anyone know something that would eat them at night. I have 3 serpent stars but don't think they would do it? My fish that are still in the tank are 2 clowns and 2 blue damsels which I would be happy to get rid of if I could only catch them. They sometimes pick on the new bees but didn't pick on the fire gobys this time around. Any suggestions? Everyone looked heathly before they dissapeard. Thanks in advance. Mike