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Reverse osmosis system with white filter housings, black pump, storage tank and faucet

Reverse osmosis system

Watts ZRO-4 Zero Waste 4-Stage RO Replacement Filters

This 4 stage RO system use sediment and carbon block pre-filters to reduce sediment, chlorine and chlorine by-products before the membrane filters out impurities larger than .001 microns. The carbon GAC post filter treats for taste and odor.

Compatible parts

Everything that fits the Watts ZRO-4 Zero Waste

Ready Water RW-SED2510050 5-micron sediment filter, direct replacement for 93023 and PX05-9 7/8
Top Seller
Ready Water
$8.99
Meets FDA requirements for food and beverage contact
Omnipure OMB934-5m 5-micron carbon block filter for standard 10-inch water filter housings
Omnipure
$14.99
Reduces chlorine, taste and odor
NSF Certified performance
USA made compression molded
2.5" Drop-in carbon block element
AXEON TF-1812-25 25 GPD thin-film composite reverse osmosis membrane, part 200357
AXEON
$37.49
Thin Film Composite (TFC)
NSF 58 Certified
Omnipure CL10ROT33-BB 5-micron inline GAC carbon filter with 1/4-inch female threads
Omnipure
$12.99
Reduces chlorine, taste and odor
NSF 42 Certified

Replacement filter info

Your replacement schedule

Each stage of the Watts ZRO-4 Zero Waste, the exact part that fits it, and when to change it.

  1. Stage 1: Sediment filter

  2. Stage 2: Carbon block filter

  3. Stage 3: RO membrane

  4. Alternative for stage 3: RO membrane

  5. Stage 4: Post carbon filter

Manuals & instructions

Manuals and guides