Water
Home water treatment: diagnose a symptom or lab result, size a softener or filter, match a model number to its part, and compare the units worth a shortlist.
Every page under this heading is about the water coming into a house: what a symptom or a test result means, what size of equipment it takes, which cartridge fits the housing you already own, and which units are worth a shortlist. Limits are cited to EPA, NSF/ANSI and extension services by number.
Sizing calculators for home water treatment: grain capacity, flow rate, micron rating and more, with the formula shown.
2 calculators
Diagnostic guides: a symptom or a lab result in, a treatment class out, with the EPA or NSF limit cited by number.
8 guides
Model number to replacement part: which cartridge, membrane or lamp fits, on what interval, and which cross-fit alternatives exist.
2 parts
System comparisons segmented by the problem being solved, chosen against a stated method from published specifications.
2 reviews
Best iron filter for well water: air injection vs manganese greensand vs Birm, by published spec
Iron plus manganese 3 to 10 mg/L: an AIO such as the AFW AIS10-25SXT (10 ppm iron) or Birm at pH 6.8 to 9.0. Under 3.0 ppm with no drain line: the iSpring WGB32BM.
Best whole-house sediment filter for well water: spin-down vs cartridge, by published spec
Coarse sand: a Rusco spin-down, 1 to 25 GPM, screens 700 to 15 micron. Fine silt: a Pentek 150233 Big Blue at 1 psi @ 15 gpm with a 5 micron nominal cartridge.
Black stains from well water: how much manganese that is and what removes it
Black stains on a private well mean manganese above EPA's secondary standard of 0.05 mg/L. Why it resists iron treatment, and which class fits each mg/L range.
Blue-green stains and pinhole leaks: low pH well water and what neutralizes it
Blue-green stains on a well are copper dissolved by low-pH water. EPA's pH range is 6.5 to 8.5; an acid-neutralizing filter treats down to pH 5.3.
Express Water WH300SCKS Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives
Express Water WH300SCKS takes FLTWH2045S1, FLTWH2045K and FLTWH2045C1 (set FLTWH2045CKS1), 4.5 x 20 in, changed every 6-12 months or 100,000 gallons.
How to shock chlorinate a well: chlorine amount, contact time, and when it is the wrong fix
Shock chlorinate a well at 50 to 200 ppm with plain 6% or 8.25% bleach, hold it 2 to 6 hours or overnight, flush to 0 ppm, retest in 2 to 4 weeks.
Iron in well water: how much is behind the rust stains, and what treats it
Rust stains on a private well mean iron at or above the EPA secondary standard of 0.3 mg/L. Which form it is, and which treatment class fits each mg/L range.
iSpring WGB32B Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives
The iSpring WGB32B takes one FP25B and two FC25B 20 x 4.5 in cartridges, changed every 6-12 months or 100,000 gallons. Pentek DGD and EP-20BB cross-fit.
Rotten egg smell in well water: hydrogen sulfide levels and what removes it
Hydrogen sulfide has no EPA limit; the nose finds it at 0.05 to 0.1 mg/L. Hot tap only means the heater anode, both taps means the well, and the mg/L picks the fix.
Tea-colored well water: tannins, how to tell them from iron, and what removes them
Tea-colored well water that stays colored after a glass sits overnight is tannins, not iron. EPA lists color at 15 units; the fix is anion resin, carbon or RO.
Water softener size calculator: grain capacity from people, hardness and iron
Grains = people x 75 gal/day x (gpg + 5 per mg/L iron) x days between regenerations. 4 people at 10 gpg for 7 days is 21,000 grains. Calculator and the size table.
What to test well water for: the annual panel, the units, and what each result decides
A private well needs coliform, nitrate, TDS and pH every year at a certified lab (CDC, EPA). Nitrate limit 10 mg/L as N. Which symptom adds which test.
White Scale on Faucets and Kettles: How Hard Your Water Is and What Fixes It
White crust on faucets and kettles is hardness scale. Hardness in gpg and mg/L (1 gpg = 17.1 mg/L), the USGS bands, and why 7.0 gpg is the line for a softener.
Whole-house filter flow rate calculator: GPM from fixtures and bathrooms
Peak gpm = showers running at once x 2.5 + one faucet at 2.2, or WQA fixture units x 0.4 + 2. A 2-bath home pulls about 7 gpm; a 20 x 4.5 in housing is rated to 15.