A cartridge filter is a highly efficient and low-maintenance pool filtration system that uses a replaceable filter cartridge made of pleated polyester or other synthetic fabrics to trap dirt, debris, and fine particles from pool water. Known for their ease of use and superior water clarity, cartridge filters are ideal for residential pools, spas, and light commercial applications where convenience and water conservation are priorities. Unlike sand or DE filters, cartridge filters do not require backwashing, which means they use significantly less water and are environmentally friendly. Instead, when the cartridge becomes clogged, it is simply removed, rinsed with a hose, and reinstalled. Depending on pool usage and water quality, cartridges typically need cleaning every few weeks and replacement every 1–2 years. Cartridge filters are available in various sizes and filtration capacities, making them suitable for pools of all shapes and sizes. Their design features a cylindrical tank housing one or more pleated cartridges that maximize surface area for efficient debris capture without a significant drop in water flow or pressure. Many systems come with easy-access lids, pressure gauges, and drain plugs to simplify maintenance.