Provides a sparkling pool day or night Filters out particles associated with recreational water illness Enhances filter productivity reducing chlorine and shock use Made from microscopic, fossilized algae, diatomaceous earth (DE) is a powder that acts as millions of tiny sponges, absorbing and trapping particles that contaminate and cloud your water Capable of filtering out particles as small as one micron, diatomaceous earth filters are the most efficient and effective pool filters available Weight: 25 lb bag\