Use the GE Merlin Reverse Osmosis Flush Kit 1268260 with, GE Merlin Tankless RO System, GE Merlin Tankless Reverse Osmosis System Replacement Filters, Stage 1: The GE Merlin Carbon Pre Filter needs to be replaced every 6 months, Stage 2: The GE Merlin RO Membrane needs to be replaced every 2-4 years, Stage 3: The GE Merlin RO Membrane needs to be replaced every 2-4 years, Stage 4: The GE Merlin Carbon Post Filter needs to be replaced every 6 months, GE Merlin RO System Replacement Parts, Housing Sump O-Rings: The GE Merlin 1240326 Housing Sump O-Rings should be replaced every couple of filter changes or when there is damage to the o-ring, Use o-ring lubricant to keep the oring effective at sealing the housing sumps, GE Merlin RO System Accessories, Optional Accessory: GE Merlin Flush Kit, Optional Part - Recommended when line pressure under 40 PSI: GE Merlin Booster Pump, SKU: CWD2098