Alkaline Remineralization Filter
Model: V21RFPH
Calcium carbonate remineralization after RO treatment. 1/4 inch quick-connect fittings.
Filter United / Individual replacements
Keep fresh-tasting water flowing. Shop individual Filter United sediment and carbon cartridges, RO membranes, inline filters, and UV components for your next filter change.
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Model: V21RFPH
Calcium carbonate remineralization after RO treatment. 1/4 inch quick-connect fittings.
Model: V21RFPC10
Coconut-shell carbon for a fresh-tasting finish. 1/4 inch quick-connect fittings.
Model: V21RFS2510
5-micron filtration for rust, sand, and particles. Standard 10 x 2.5 inch cartridge.
Model: V21RM100
Thin-film composite membrane for RO dissolved-solids reduction. Select your capacity below.
Model: V21RM75
Thin-film composite membrane for RO dissolved-solids reduction. Select your capacity below.
Model: V21UVLED
UV LED treatment component for compatible RO installations.
Model: V21RFG2510
Coconut-shell granular activated carbon for RO prefiltration. Standard 10 x 2.5 inch cartridge.
Model: V21RM50
Thin-film composite membrane for RO dissolved-solids reduction. Select your capacity below.
Model: V21RFC2510
Chlorine, taste, and odor control. Standard 10 x 2.5 inch carbon block cartridge.
Helpful details
Sizes, capacity options, and filter care.
Our standard sediment, carbon block, and GAC cartridges use the common 10 x 2.5 inch format for compatible conventional RO prefilter housings. Use the dimensions and cartridge design on your existing part to match your replacement.

Select the 50, 75, or 100 GPD capacity specified for your system using the dropdown on the membrane card, then add it to your cart. Your current membrane label is a useful reference. For a capacity change, confirm the membrane housing and flow-restrictor requirements with your system instructions or our team.
Carbon block uses compressed activated carbon; GAC uses granular activated carbon. Both are used for chlorine, taste, and odor treatment. Choose the media type shown in your system's filter sequence.

The post-carbon filter polishes taste after RO treatment. The alkaline filter adds calcium carbonate mineral media after RO treatment. These listings use 1/4 inch quick-connect fittings; match your existing filter's connections, flow direction, and available space. Final pH depends on water and operating conditions.
Open the V21UVLED product page for the component information. Use its installation instructions for electrical, connection, and flow requirements. Our team can help with questions about your setup.
Follow your system manual for shutoff and depressurization, then replace the specified cartridge and inspect the seals. Restore the supply, check for leaks, and complete the directed flushing procedure. Follow each component's service schedule. Powered UV servicing requires its own instructions.

Your next filter change