My yellow tang has a white film over its left eye. It sticks out a little over the eye. Anybody know what this is and what I can do. Any help would be appreciated.
Sounds like the beginnings of popeye--usually the result of poor water conditions. Run some tests and see what your ammonia and nitrites are right now. Water changes might help--otherwise you may need to isolate the tang for medicating.
Is this a fairly new setup? The nitrite shouldn't be that high in an established tank. Lots of water changes will help, but you'll want to figure out why the nitrites are even present, if this is an established tank.