The Tier1 RO5 Filter Set 1 is a complete annual replacement pack designed specifically for Tier1 5-stage reverse osmosis systems. It includes three pre-filters: a 5-micron sediment filter (Stage 1) to capture dirt, rust, and sand; a 5-micron GAC (granular activated carbon) filter (Stage 2) to reduce chlorine, taste, and odor; and a 5-micron carbon block filter (Stage 3) to further reduce chlorine and organic contaminants before water reaches the RO membrane. This set does not include the RO membrane (Stage 4) or post carbon filter (Stage 5), which have longer replacement cycles.

The Tier1 RO5 Filter Set 1 pre-filters (Stages 1–3) should be replaced every 6 to 12 months, depending on your household water usage and incoming water quality. Replacing these filters on schedule is essential to protect the RO membrane from premature fouling, maintain optimal flow rate, and ensure your Tier1 RO5 system continues to deliver clean, great-tasting drinking water. Homes with higher sediment or chlorine levels may need replacement closer to the 6-month mark.

This Filter Set 1 is engineered to fit Tier1 5-stage reverse osmosis drinking water systems that use standard 10-inch filter housings. The 5-micron sediment, GAC, and carbon block filters are sized to drop directly into Tier1 RO housings without modification. Always confirm your system uses 10" x 2.5" filter cartridges before ordering. This set is not intended for non-Tier1 RO systems with proprietary housings or quick-connect cartridges.

All three pre-filters in the Tier1 RO5 Filter Set 1 are rated at 5 microns. The Stage 1 sediment filter removes particulate matter such as sand, silt, rust, and dirt down to 5 microns. The Stage 2 GAC carbon filter reduces chlorine taste and odor along with many organic chemicals. The Stage 3 carbon block filter provides a final polish, reducing residual chlorine, VOCs, and fine particulates before water passes through the RO membrane—protecting membrane life and improving overall water quality.

Yes, it's recommended to sanitize your Tier1 RO5 system each time you replace the Filter Set 1 pre-filters. Turn off the feed water and drain the storage tank, then remove the old filters and clean the housings with warm soapy water. Add a few drops of unscented household bleach to the first housing, reassemble with new Tier1 filters, and flush the system by running water through the faucet for several minutes until any chlorine taste is gone. Also flush the storage tank 1–2 times before drinking to ensure the water is fresh and safe.