Diatomaceous Earth (D.E.) Powder (25 Pounds) is a high-grade D.E. filter powder that can filter down to 3-5 microns in size and leave water sparkling and crystal clear without clumping. This D.E. powder is porous, all-natural, and created from the fossilized exoskeletons of plants, known as diatoms. It delivers an astounding level of filtration and ensures efficiency, so your filter will always operate at its peak level. This D.E. powder not only leaves water shimmering and sparkling with clean, pure beauty, but it will also reduce the amount of time you spend maintaining your pool and save you money on pool supplies.