Our Bettas have experienced this twice. We have tiny little (almost microscopic) white things floating in the tank. I don’t think it’s ich. We thought maybe dust got in the tank the first time. We cleaned it out with boiling water and used Campden pellets to clean. It’s been a few months, and now they are back with a vengeance. Usually, you see them floating all around in the water. They don’t just float...they move with purpose. We keep our tanks clean - he was in a 5 gallon. We took our Betta (Endumnd) out and put aquarium salt and Campden pellets in the tank. The salt seemed to kill them last time. Well, now they have congregated around the pellets...it’s eerie. Ugh - does anyone know what the heck these evil little things are?? I’m at a loss - I want them gone, and I want them to stay gone.