Im really scared for my clown. It was a single fish, maybe 1 1/2 inches long by himself in a tank. Completely healthy, eating like a pig, and just starting to host in a frogspawn. Yesterday I put in a juvenile purple tang, maybe twice his size. Watched them for a little while and they seemed okay with each other. Woke up this morning and saw all of this white gunk on him and his fins are a little torn, he also completely lost his appetite, is running into the tank walls, and is really lethargic. Is the purple tang beating him up or is it some kind of illness?