There's a post in the diseass forum called "Betta has ick" or something like that (it should be the first one you see). In it, I detail out how to treat ick without meds and in the most efficient way. Basically, gradually crank your heat up to 85-86F and keep it there for two weeks at least. This will kill the ick parasites and spores. Do bi-weekly 20% water changes, making sure to vacuum the gravel REALLY WELL to pick up the dead and dying spores. Usually after two weeks of the hight temps, your tank will be ick free, but you might want to keep the temp up for a third week, just to be on the safe side. Make sure you add an air stone or other type of aeration to the tank because the higher heat will deplete the oxygen in the water.