Cotton mouth disease?

If the others have died, I'm not sure its terminal but it's not early stages either. Kanamycin, a combo treatment of Maracyn and Maracyn 2 (works best), API Fungus Cure or Triple sulfa will cure the Columnaris flexibacter infection. My mother, who has Bettas uses Fungus Cure and it has worked 3 out of 3 times.