Question for any one who has had a saltwater aquarium that has been successful in keeping fish! In the last three days I have lost a healthy yellow tang a blue spot jaw fish and a potters angel, my water parameters are all spot on except my ammonia is .15 and it should be zero all of my corals look fine. The two clown fish and my dragon head are fine, both cleaner shrimp are alive and my coral banded shrimp is fine. Is there anything that anyone can think of that would kill off three healthy fish in a few days time without affecting the other stuff in the tank? I am stumped and need assistance super fast so please any help would be greatly appreciated!!!