What do you think this is and how would I go about treating it? The fish is currently in a tank 55g bare bottom tank with nothing in it, but a purple tang(possibly the carrier).
Click here for a short video.
This either came from my Eel which I have had quarantined for 10 weeks now. I could have possibly used the same net or accidentally switched heaters with out washing them out enough or something. The other possibility is the purple tang, which I recently added, had it and was immune. The tank it came from also had a clown fish and some chromis which had been doing fine for a very long time, so I don't know. Investigating and researching now.