Hi. I have had my bettas for three weeks now. Given as a gift for my son from my stepdaughter, they both had some fin rot when I first brought them home. I treated them with aquarium salt baths for four days, about ten minutes a day. I don't currently add aq salt to their tanks. My blue one has healed beautifully, but my red one still has some black at the edge of his tailfin, however I am noticing a lot of fin regrowth on all of his fins. My question is, did I treat him long enough with the salt baths? I have him in a filtered, heated 1Gal and I do 100% water changes every other day.