I got a new boy about 3 weeks ago who was chewing his tail. I thought he was getting better, but I just went and checked on the boys and his tail is even worse. It definitely looks like chewing and not finrot, what should I do, I have just done a water change and added salt. Should that be ok? he's in a 1 gallon with a plant and several feet away from any other betta, I can't figure out why he's chewing. He flares at everything, but I've never actually seen him chewing.