Help diagnosing betta

Question
I have had my betta for about 6 months. Recently, he has started laying around the bottom of his tank, and although he is a dark colored betta, he seems pale. He keeps his fins clamped together, which appear to have developed red and dark tips. Because the fins also seem a bit thinner,I took these to be signs of fin rot and have been treating him with kanamycin for a week now. He has shown almost no improvement. Other than these symptoms, I can't identify any signs of disease. Other facts regarding care are: tank temperature is between 75-80 F, water quality tests safe, water changes once a week, 1 gallon tank, and fed flake food 2 times a day, three times a week.

Answer
Viruses can only be seen through microscopes - and its incurable. With a bacterial disease, use a anti-bacteria or anti-internal treatment. A prolonged SALT bath (3-5 g/litre for several days) will alliviate osmoregulatory stress in the case of severe ulceration.