The Bestway 58500E FlowClear Sand Filter 2200 gal 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.