STAGE 1 – TWIST-IN SEDIMENT FILTER CARTRIDGE. Aquatic Life Twist-In Sediment Filter Cartridge: Recommend replacing every 6 months. 5-Micron Sediment Filter that traps sediment and other particulate matter like dirt, silt and rust which will affect the taste and appearance of your water. Working Pressure: Minimum 35 PSI, Maximum 80 PSI, Ideal 65 PSI.