I dont know if it's a rash or some kind of wound. It just popped up yesterday. My water was in really bad condition since a couple of week, I was too busy else where, today i did a full water change, gave him a salt bath. Let's see how he would do.Hi
I would keep your water really clean and treated. Meds im not sure whats safe for sensitive fish, i keep elephant nose fish and when they get cuts i just keep the water warm and clean and it always helps them. How did it get injured? Do you have sharp objects its got caught on or another fish?