I think my betta has finrot because I noticed his fins are looking a little raggety. a few days ago I noticed a little piece of fin had partially come off, and today I noticed a couple more little strands partially hanging. He has been moving around less since a week ago. I'm planning on treating him with aquarium salt (2 1/2 tsp everyday with 100 percent water changes.) I'm wondering, I have kanaplex on hand, so should I treat him with it? I'm not sure if the finrot is advanced enough that it's neccesary? also, is kanaplex a good choice, or should I buy another medication like maracyn? Also don't know if I should use the kanaplex because I heard that it can lower the oxygen level-- so does he need a filter on to make sure he gets enough oxygen? I don't want to put him in my tank with a filter because I heard finrot is contagious and there are other fish in there. And I don't know if it's a good idea to treat all my healhy fish with kanaplex since it can cause kidney damage? I could treat him in a seperate tank but it doesn't have a filter.