CUNO SQC 4-Stage RO Replacement Filters

The CUNO/WaterFactory 4 stage RO system by 3M uses sediment and GAC pre-filters to reduce chlorine, chlorine by-products and sediment before the membrane filters out impurities larger than .001 microns. The carbon block post filter treats for taste and odor. Be aware that 3M has started to update some of the older part numbers to part numbers starting with 3M but are the same as prior part numbers. You can find and order all your filters at once in our replacement kits below. For less expensive generic replacements, please look at our Omnipure CSM brand.

Replacement Filter Info

Sediment Filter (3MROP311 or CSM5651) – Replace Every 12 Month

Carbon Block Filter (3MROP416 or CSM5621) – Replace Every 12 Months

RO Membrane TFC 36 GPD (3MROM413 or CSM5672) – Replace Every 24 Months

Carbon Block Filter (3MROP412 or CSM5640) – Replace Every 12 Months

Helpful Filter Information

Not all filters have the same replacement schedule. Replace the RO membrane filter every two years. Replace all other filters every 6-12 months. Help keep your system sanitary by never using filters longer than 12 months, except the RO membrane filter, regardless of how much water you use.

Filter Replacement Schedule

We’ve taken the guesswork out of replacing your filters. Begin a filter replacement cycle by replacing all filters on your system (Filter Kit "YSM"). The following year, or sooner if recommended by the manufacturer, replace all filters except the RO membrane (Filter Kit "YS"). Repeat this cycle by following the helpful diagram below.