I bought a healthy looking fox face rabbit fish and like an ------- I just put him in the tank. He looked great for 2 days but didn't eat,thought was just scarred, but last night his fecal matter looked exactly like he was passing a 1 inch worm but I caught the matter with a net and it is not a worm, but a very mucusy looking stool. Not the thin,clear kind that trails behind the fish. This was a thick round mucus looking, not exactly clear matter. I caught him this morning and he is where he should have been before. I KNOW. Anyway ,what do you think this is and how should I treat it. Upon looking up fish diseases,it exactly sounds like Hexamita, but I'm not sure if this is a salt water disease.