Cartridge filters have the second-best filtration capability out of the three other available filters for pools and spas. They are capable of filtering down to 10 - 15 microns. This provides better water clarity when compared to sand filters. Cartridge filters do not require backwashing, making them the most eco-friendly filter option. They also work great with variable speed pumps. Allowing them to filter more effectively at lower flow rates. When the pressure in the filter increases 8 - 10 PSI above the starting pressure, remove the filter(s) from the tank and hose off to clean. It’s recommended to replace your filter(s) every 2 - 3 years depending on use. Here at PoolSupplyWorld, we offer all the most reliable and popular manufacturers and brands such as Hayward, Waterway, Pentair, and many more! If you have any questions or concerns please feel free to contact us at 1-800-772-0467 or chat with us online at www.poolsupplyworld.com.