I was feeding my 3 12" oscars and one had a gash in it's side so i caught it and took pictures and could not figure out what it is. The oscars tank mates are a 26" adonis pleco (added 2 days ago) a 26" red tail catfish, a 20" ripsaw catfish, 3 adult servums, 2 nicoruguran cichlids, and other large oscars. This oscar looked gravid and i was going to put it into it's own tank (if i can get one empty) to try to breed them. Recently i started to feed the oscars crayfish every 4th day and they eat cichlid gold every day. The skin has ripped and is only on one side of the fish. If this is contagious i will have to put the fish into a large gallon rubbermaid tub to treat (4 feet by 3 feet, and 1.5 feet tall), would prefer i will put meds to help it heal into the main tank so i don't have a bucket on the ground. Any guesses or suggestions are appreciated because if i might be able to save this fish with meds or salt , i will try. Thank you.