Armstrong HumidiClean™ is going to change everything you know about humidifiers. Ionic beds are made of a fibrous medium that attracts solids from the water as its temperature rises. This minimizes the buildup of solids on inner tank walls and heating elements. So you have a humidifier that stays clean except, of course, for the ionic beds. And once they have absorbed their capacity of solids, the humidifier alerts you that it’s time to change them. It takes about 15 minutes, and it’s absolutely hassle-free.