Dry Earth™ is made from a natural stone, we use this substance in the form of a disk at the base of your favorite bathroom essentials. Used to absorb excess water and prevent mold, this anti-bacterial powerhouse is a real game-changer in the bathroom. Diatomaceous earth gets its name from what it’s made of—diatoms, or tiny aquatic species that accumulate in our waterways. Diatomaceous earth is essentially a collection of fossilized remains. It’s high in silica, so it’s used to treat certain health conditions. Use this Dry Earth™ Disk to replace the disk at the bottom of the Keep It Clean Toothbrush Holder every 6 months.