The Flowclear™ 1500 gal. Sand Filter from Bestway® is a highly efficient and environmentally friendly way to keep clean water flowing through your above ground pool. It is a more cost effective solution as the pump uses silica sand instead of a traditional filter cartridge. While those cartridges need to be replaced every 2 weeks, silica sand lasts up to 3 years. The sand will trap dirt and debris, but a pre-filter strainer basket catches larger things so that the pump will last longer. The filter also comes with the ChemConnect™ Dispenser, which maintains clean, healthy water by providing a stable level of chlorine that is evenly dispersed throughout the pool. This product comes pre-assembled, and is compatible with most 300-11,200 gal. (1,100-42,300 L) above ground pools, as it comes with an adapter for pool valves with an outer diameter of 1.5 in (3.8 cm). The sand is not included with this filter - required sand size is #20 silica sand, 0.45-0.85 mm, approximately 9 kg. The filter also works wonderfully with Bestway’s Polysphere™ Filtration Balls.