The Geopress replacement filters are designed for a service life of 300 cycles (150 l). Life is reduced when cleaning water with high levels of silt, sediment or tannins. Cartridge press time increases toward the end of cartridge life. When the press time reaches 25-30 seconds, the cartridge should be replaced. Even though the cycle time increases, the cartridge continues to protect. It is recommended that the cartridge then be replaced at some point, despite any environmental concerns.