Spec sheetTop pick
ClearFlow Grade · Water Treatment Lab
ClearFlow Grade
Expert reviews, honest comparisons, and the best deals on Water Filters — helping you make smarter buying decisions.
- Systems on the bench
- 8
- Buying guides
- 12
- Treatment paths
- 6
The System Matcher
What system does your water call for?
Enter your measured water hardness and household size. We run the published Water Quality Association sizing formula to point you to a system class and an illustrative annual filter cost — a starting estimate, not a tested result.
From your utility's water report or a test kit. 1 GPG = 17.1 mg/L (ppm).
Sizing assumes the WQA estimate of 75 gallons per person per day.
Where the formula points
32,000-grain water softener
Extremely hard water · target 32,000-grain
Illustrative annual salt cost: about $80–$150 (varies with hardness and use)
Published WQA sizing: 4 people × 75 gal/day × 15 GPG = 4,500 grains/day, ×7 days ≈ 31,500 grains of weekly capacity. The smallest standard class that clears that is shown — size up if you host guests or have well-water iron.
Read the matching buying guides
Illustrative only — figures come from published WQA sizing formulas and market price ranges, not a physical test. Well-water iron, flow rate, and salt efficiency change the right pick; verify specifications on the retailer's listing before buying.
On the bench
Systems on the bench
Every filtration system and softener we cover, read off its published spec sheet — grain capacity, stages, and rating, not a paid placement.
Spec sheetTop pick
Spec sheetTop pick
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Spec sheet
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Spec sheet
Treatment paths
Explore by Topic
Pick the problem you're solving — hardness, well-water iron, drinking-water taste — and we'll point you to the published comparisons that fit.
Whole-House Filtration SystemsPoint-of-entry carbon and tank-based systems that filter every tap in the home.3 guidesWater Softeners & ConditionersSalt-based softeners and salt-free conditioners for hard-water homes.2 guidesReverse Osmosis SystemsUnder-sink and tankless RO systems for high-purity drinking water.3 guidesUnder-Sink & Countertop FiltersCompact point-of-use filtration for kitchens and rentals.1 guideWell & Problem-Water TreatmentSediment, iron, sulfur and pH treatment for private-well and problem water.2 guidesFilters, Cartridges & MaintenanceReplacement cartridges, salt, and the annual upkeep cost of owning a system.1 guide
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