Pool Filter 20-Grade Silica Sand (50 Pounds) is the worry-free, hassle-free choice to keep swimming pools clean and crystal clear. It does not stain and ensures easy maintenance at a lower cost by filtering out dust, algae, suntan lotion, oil, leaves, and insects. Ecologically safe, this sand does not solidify and will help prevent clogging and channeling. It is inert and odorless, 100% natural, and chemical-free. Used for both residential and commercial sand filters, this pool filter sand backwashes easily and evenly.