Hello. I have a sick koi. I saw him acting weird on Monday. He was alone, not eating, and hanging out by the bottom of the pond (5 feet down). Tuesday afternoon I found him laying on his side gasping. I put him in a hospital tank. He had no obvious sores, cuts, film, etc. I added stress coat to the tank and some Pimafix. Wednesday his breathing was worse, but his body still looked fine. At night, he started having white film coming off his body. Thursday he had a good 1-2 inches of film attached to his body. The film is also on the gravel on the bottom of the tank. It isn't on all of the rocks, it seems like only the ones he has been laying on. I was told to use Pimafix and Melafix. My koi's breathing is back to normal, but the film is still there. The medication doesn't seem to be doing anything-but it is still early. Any ideas what the film is?