I have two discus in my tank that I have had for 3 weeks. I have been feeding a variety of foods recently and I have been making 30% water changes once every week. The ph is 6.0, the temperature is 80 degrees F. The ammonia, nitrite and nitrate levels are all fine also. Three days ago I bought frozen blood worms for my discus and the loved them. A day or 2 after feeding the bloodworms every morning for breakfast one of the discus appeared to have darkened and on one sid of him he has a white, decaying, filmy looking spot right by his fin. He keeps that fin closed most of the time. I also noticed his poo is clear and jelly like. he still eats, but he is not as active as he used to be. The other discus is fine. I am going to buy a UV sterilizer for my fish tank tommorow and i am hoping it will help, as I have had some people say that a UV cleared up these similar symptoms for their discus. Will the UV help? I also want to know if the UV will take blackwater extract out of my water and the yellow tannin it creates.
Thanks for the help!