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.
15 calculators
Diagnostic guides: a symptom or a lab result in, a treatment class out, with the EPA or NSF limit cited by number.
57 guides
Model number to replacement part: which cartridge, membrane or lamp fits, on what interval, and which cross-fit alternatives exist.
49 parts
System comparisons segmented by the problem being solved, chosen against a stated method from published specifications.
30 reviews
Best well pump, jet and submersible: Red Lion and Goulds spec sheets sorted by depth to water, then GPM at a stated depth and pressure, because the depth picks the type before the horsepower
Depth to water picks the type: under 25 ft a shallow jet (Red Lion RJS-75, 7.2 GPM at 25 ft, 40 psi), 25 to 90 ft a convertible, deeper a 4 in submersible (RL12G10).
LG LT600P Refrigerator Water Filter: Part Numbers 5231JA2006A and 5231JA2006F, the Kenmore 469990 Twin, and Which Cross-Fits NSF Lists
LG LT600P (5231JA2006A / 5231JA2006F) is rated 300 gallons or 6 months; NSF lists it at 0.5 gpm to NSF/ANSI 42 and 53, with lead and cyst reduction.
Well pump size calculator: GPM from your fixture count, capped at the well's yield, with the pump type for your depth
Pump gpm = fixtures x 1 gpm (Water Systems Council, Red Lion): an 8-fixture house takes an 8 gpm pump, never above the well yield, submersible past 90 ft.
Aquasana AQ-5200 Claryum 2-Stage Replacement Filters: The AQ-C2-R (AQ-5200R) Set, Its Rating and What Else Fits
Aquasana Claryum 2-Stage AQ-5200 and AQ-6200 take the AQ-C2-R set (AQ-5200R): 500 gallons or 6 months, 0.5 gpm, WQA to NSF/ANSI 42, 53, 401 per Aquasana.
GE GSWF Refrigerator Water Filter: Which GE Top-Freezer and Bottom-Freezer Models Take It, the 300 vs 750 Gallon Question, and Which Cross-Fits NSF Lists
GE GSWF twist-and-lock cartridge: GE says 6 months, prints both 300 and 750 gallons, and has stopped making it. Which cross-fits NSF lists to 42, 53 and 401.
How long does a water softener last? Which part fails first, what the makers warrant, and when to repair instead of replace
No maker document read here prints a lifespan. Pentair warrants Fleck valves 5 years; Dow gives resin 10 years under 0.2 ppm chlorine, 6 at 1 ppm.
Water softener vs water filter: what each one removes, and why many homes need both
A softener swaps calcium and magnesium for sodium under NSF/ANSI 44 and leaves chlorine, lead and PFAS alone. A carbon filter (NSF/ANSI 42 or 53) does the reverse.
Best refrigerator water filter: the genuine cartridge for each fridge family, bought by the number on the old cartridge and judged by the certifier's listing row, not the brand on the box
Genuine cartridges by maker document and certifier row: Frigidaire EPTWFU01 IAPMO R&T 42, 53, 401 at 125 gal; everydrop EDR1RXD1 NSF 200 gal; GE XWFE 170 gal.
Best well pressure tank: Amtrol, Water Worker, Goulds, Pentair, Wellmate and Reliance by maker spec sheet, sized on drawdown against pump GPM rather than the gallon label
Maker sheets compared: Amtrol WX-203 prints 8.6 gal drawdown at 40/60, WX-202 5.4, WX-250 11.8; sized on pump GPM and a 1 minute run. Pre-charge 2 psi below cut-in.
Best whole house water filter and softener combo: the maker spec sheets sort them into salt-based sets that remove hardness and salt-free sets that do not, and the hardness number decides
AFW Fleck 5600SXT 48K with upflow carbon: 48,000 grains, 12 gpm, 1.5 cu ft carbon. Aquasana SimplySoft 60K prints NSF/ANSI 44; Kind and SpringWell are salt-free.
Brita vs PUR vs ZeroWater: which pitcher filter is certified for lead and PFAS, by whom, and for how many gallons
Brita Elite (WQA, 120 gal), PUR PLUS (WQA lead rows, 40 gal) and ZeroWater (IAPMO R&T, 15 gal) carry a certified lead claim; Brita Standard and plain PUR do not.
Frigidaire EPTWFU01 PureSource Ultra II Filter: What It Is Certified For, How It Differs from ULTRAWF, WF3CB and FPPWFU01, and Which Cross-Fits Are NSF Listed
Frigidaire EPTWFU01 PureSource Ultra II: 125 gal, 0.65 gpm, 6 months, IAPMO R&T certified to NSF/ANSI 42, 53 and 401. NSF-listed cross-fits are 200 gal at 0.5 gpm.
Generic vs OEM Refrigerator Water Filter: Is a Generic as Good, and How to Check the NSF Listing Instead of the Box
Neither OEM nor generic is certified by default. Look the model up at NSF, WQA or IAPMO: genuine EPTWFU01 is IAPMO-certified to 42, 53, 401; some generics 42 only.
Well pump not working, no water: the six checks in the order a homeowner can make them
No water from a well: read the gauge against the switch cut-in (30 or 40 psi), check the breaker, the switch contacts, the tank pre-charge 2 psi below cut-in.
Well Pump Pressure Switch Replacement: Square D Pumptrol FSG2J20, FSG2J21 and FSG2J24 for 20-40, 30-50 and 40-60 psi
Read the pressure pair off the old switch. Square D Pumptrol FSG2J20 is 20-40, FSG2J21 is 30-50, FSG2J24 is 40-60 psi; add M4 for a low-pressure cutoff.
Reverse osmosis Black Friday and Prime Day deal check: the GPD rating, the drain ratio and the NSF/ANSI 58 listing decide whether the discount is on the right unit
Prime Big Deal Days run October 6-7, 2026. Before buying RO on sale, check GPD at your pressure (APEC: 50 GPD at 60 psi, 30 at 50), drain ratio and NSF/ANSI 58.
Water filter Black Friday and Prime Day deals: the discount only counts if the NSF/ANSI standard matches your water
A discounted water filter is a deal only if it carries NSF/ANSI 42, 53 or 58 for your contaminant in a certifier's listing. Prime Big Deal Days: October 6-7, 2026.
Water softener Black Friday and Prime Day deal check: size the grains before you trust the discount
A softener deal is only real if the grain capacity fits: gpg (plus 5 per ppm iron) x people x 75 gal x days. The box number is the max-dose capacity.
Best countertop water distiller for the US, UK/EU and Japan: watts, hours per batch, glass or plastic, stainless grade and warranty, by published spec
Megahome MH943SBS is the US pick: 580 W, 1 gallon per 5.5 hours, glass collection, UL listed, 1 year. Eight 120 V, 230 V and 100 V units on maker spec.
Shower Filter Replacement Cartridge by Model: AQ-4125, WHR-140, HOC, SLC, SFC100 and the Gallon Rating Behind Each
Aquasana AQ-4100/4105 take AQ-4125 (10,000 gal or 6 months), Culligan WSH-C125 takes WHR-140, Sprite HO2 takes HOC (25,000 gal), SL2 takes SLC, SF100 takes SFC100.
Water distiller cost per gallon calculator: kWh, electricity cost and hours per gallon or litre
kWh per gallon = watts x hours per batch / gallons. An 800 W distiller at 4 hours a gallon uses 3.2 kWh, about 59 cents at EIA's July 2026 18.31 cents per kWh.
White dust from a humidifier: it is the minerals in the fill water, and a softener will not stop it
White dust from an ultrasonic humidifier is tap-water minerals in the mist, per EPA. Distilled or RO water stops it; softened water only swaps calcium for sodium.
Are water softeners banned where I live? What the statute actually says, and how to check your own address
No US state bans residential water softeners. California HSC 116786 lets a local agency prohibit installation by ordinance, and only prospectively.
Boil water notice: what boiling fixes, what it does not fix, and what to do once it lifts
CDC says 1 minute at a rolling boil, 3 above 6,500 feet. Boiling handles microbes and does nothing for lead, nitrate or PFAS. Here is the full procedure.
Chromium-6 in California tap water: a 10 ug/L state MCL, phased by system size from 1 October 2026
California's hexavalent chromium MCL is 0.010 mg/L (10 ppb), effective 1 October 2024. Compliance starts 1 October 2026 for systems with 10,000 or more connections.
Flooded well: what to do first, in the order that keeps the pump and the plumbing out of trouble
A flooded well: power off and an electrician first, purge until clear, then disinfect, then a certified lab test at 7 to 10 days, 2 to 4 weeks and 3 to 4 months.
How to look up your own water system's PFAS results in EPA's UCMR 5 dataset
EPA's final UCMR 5 dataset, released August 2026, covers about 10,130 water systems. Find your PWSID, read the result, and know why a non-detect means below 4 ppt.
How to read your Consumer Confidence Report: the violations sections, range versus average, and the lead line that is not about your tap
A CCR is due by July 1 and covers mandatory monitoring only. The lead line is a 90th percentile of up to 100 homes, and data can be 5 years old.
Lithium in drinking water: no federal limit, and 26.6% of systems above EPA's 10 ug/L reference level
EPA's UCMR 5 found 2,747 of 10,313 public water systems above the 10 ug/L lithium reference level. That level is a screening value, not an MCL.
Refrigerator Water Filter by Model Number: How to Find Which Cartridge Your Refrigerator Actually Takes
GE publishes no model-to-filter table. Read the old cartridge code, find the model number label, and route to the right cartridge across 6 brand families.
Well Pressure Tank Cross-Reference: WX-202, HT-20B, V60, WR 60 and RL20A by Capacity Class
Amtrol WX-202, Water Worker HT-20B, Goulds V60, Flexcon WR 60 and Red Lion RL20A share the 20-gallon, 1 in slot. Drawdown at 40/60 psi: 5.3 to 5.9 gal.
Well winter freeze checklist: the pitless adapter, the pressure tank, the hydrant and where heat tape does not belong
A well freeze checklist: Minnesota code buries supply pipe 12 inches below the local frost depth, and a pitless adapter attaches 6 or 7 feet down.
Wildfire water advisory: why the notice says do not drink and do not boil
EPA says boiling wildfire-impacted water could create an inhalation risk until VOCs are ruled out. Benzene's federal MCL is 0.005 mg/L. Read the notice type first.
Your lead service line notice arrived: what the category means and what to do about it
The annual lead service line notice goes out by 31 December. What lead, GRR and unknown mean, and the 30-day clock you start by disputing the category.
Best 20 inch Big Blue filter housing: port size, 90 psi rating, material, wrench, bracket and NSF/ANSI 42, by published spec
Pentek 150233: 1 in NPT, 90 psi max, NSF/ANSI 42 listed housing. iSpring WGB32B if you want a full 15 GPM system with wrench and bracket in the box.
Best gravity water filter: Berkey alternatives compared on stated NSF/ANSI standards, element life and tank size
LifeStraw Home states NSF/ANSI 42, 53, 401 and a 264 gal membrane; Waterdrop King Tank states 42, 372 and 6,000 gal carbon. No listing confirmed.
Best water softener resin cleaner: iron-specific vs general cleaners, dose per maker label, and who should skip one
Iron fouling: Iron OUT powder, 1 cup per 0.5 gal, then 0.25 cup per 40 lb salt. No iron: Res Care at 4 oz per cubic foot. No fouling: skip it.
Black specks in water after a new carbon filter: carbon fines, manganese or rubber, and how much to flush
Black specks after a filter change are carbon fines: GE says flush 2 to 3 gallons. Specks that outlast the flush point to manganese at 0.05 mg/L or rubber.
Bluevua RO100ROPOT Replacement Filters: Which Filter Fits the RO100ROPOT and RO100ROPOT-UV, and How Often to Change Each One
Bluevua RO100ROPOT and RO100ROPOT-UV take the same PP, CTO, RO and PCF filters: 12 months for PP, CTO and PCF, 12-24 months for the RO membrane.
Brita Faucet Filter Replacement: Which Mount Takes the FR-200, What Basic, Complete, Elite and Elite Advanced Mean, and the Cross-Fit That Claims to Fit
Every Brita faucet mount (FF-100/SAFF-100, Elite or Elite Advanced) takes the FR-200: 100 gallons, 0.58 gpm, WQA-certified to NSF/ANSI 42, 53 and 401.
Cloudy or milky tap water: the glass test that separates dissolved air from turbidity, zinc and methane
Milky water that clears bottom-up in about 1 minute is dissolved air. Water that stays cloudy is turbidity; EPA caps public systems at 1 NTU.
DREO Reverse Osmosis Replacement Filters: Which Cartridge Fits the RO Water Filter 112 and the RO Water Filter 511
DREO RO Water Filter 112 takes one 265 gallon combo cartridge; the 511 takes DR-KPA018 (about 1,050 gallons) or DR-KPA017 plus the 6 month DR-KPA016.
Frigidaire WF3CB PureSource3 Filter: What Fits, Which Cross-Fits Are NSF Listed, and Why the EPTWFU01 Is Not the Same Cartridge
Frigidaire WF3CB is the PureSource3 cartridge. Its NSF-listed cross-fits are rated 300 gal at 0.5 gpm to NSF/ANSI 42; the EPTWFU01 is a different 200 gal element.
LG LT800P Refrigerator Water Filter: Part Numbers, What Fits, Cross-Fit Alternatives and How It Differs From the LT700P and LT1000P
LG LT800P (ADQ73613401, ADQ73613408) is rated 200 gallons or 6 months, NSF/ANSI 42 and 53 per LG's page; ICEPURE's cross-fit lists 42 and 372, not 53.
Low water pressure after installing a whole-house filter: port size, micron rating, a loaded cartridge or a bypass valve, and how a gauge tells them apart
A 20 x 4.5 in Big Blue housing drops 1 psi at 15 gpm with 1 in ports and 2 psi with 3/4 in ports per Pentair. A gauge on each side finds the cause.
Reverse osmosis tank not filling or faucet running slow: the six causes, the check for each, and the pressure numbers that decide it
RO tanks stop filling below iSpring's 45 psi feed minimum or with precharge under 5 to 10 psi empty. Six causes, the gauge check for each, the fix.
Reverse osmosis water tastes bad: what flat, plastic, salty, rotten-egg and chlorine tastes each mean and what fixes them
Flat RO water is normal: NSF/ANSI 58 requires 75% TDS removal. Salty means the membrane, rotten egg means sanitize, chlorine the post-filter.
Samsung DA29-00003G Refrigerator Water Filter: Why It Is the HAFIN1/EXP and Not the HAF-CIN, What It Replaces and Which Cross-Fits Match
DA29-00003G is Samsung's HAFIN1/EXP cartridge for head DA97-06317A, not the 300-gallon HAF-CIN DA29-00020B; the ICEPURE cross-fit lists NSF/ANSI 42.
Softened water sodium calculator: milligrams per glass and per day from your hardness number
Sodium added = 8 mg/L per gpg of hardness removed (NDSU). 15 gpg softened water carries 120 mg/L: 28 mg per 8 oz glass, 240 mg in 2 L a day.
Water filter cartridge life calculator: how many days a filter lasts from its gallon rating, your daily use and the maker's month cap
Days = rated gallons / gallons per day, capped by the maker's months. A 40-gallon, 2-month Brita Standard at 0.5 gal/day lasts 60 days, not 80.
Well shock chlorination bleach calculator: casing gallons, target ppm and cups of bleach
Casing gallons = 0.041 x diameter squared x feet of water. A 6-inch well with 100 feet holds 148 gal and takes about 4 cups of 6% bleach at 100 ppm.
Whirlpool EDR2RXD1 (everydrop Filter 2): Which Refrigerators Take It, What It Replaces, and What Is Actually Published
everydrop Filter 2 EDR2RXD1: 200 gallons or 6 months, NSF/ANSI 42, 53 and 401, 70 contaminants including 99% of microplastics, per Whirlpool's own product page.
White flakes or particles in ice or the kettle: hardness scale, dip tube plastic, resin beads, or trapped air
White flecks that fizz in vinegar are hardness scale: 1 gpg is 17.1 mg/L per MSU Extension. Floating plastic curls are dip tube; amber beads are resin.
Whole-house water treatment install order: where the sediment filter, softener, carbon filter and UV go, and why
Well: tank, sediment, iron fix, softener, carbon, UV last, since Viqua caps UV inlet at 7 gpg and 0.3 mg/L iron. City: sediment, carbon, softener.
Acid neutralizer size calculator: calcite or Corosex tank size from pH and peak flow
Bed area = peak gpm / 5 for calcite (pH 6.0-7.0) or / 3 for a calcite-Corosex blend. A 2.5 gpm home at pH 6.8 needs a 10x54 tank and 98 lb of calcite.
Aquasana Claryum AQ-5300 Replacement Filters: Which Set Fits the AQ-5300, AQ-5300+, AQ-5200 and Direct Connect
Aquasana AQ-5300 takes AQ-C3-R (600 gal), AQ-5300+ takes AQ-C3M-R (800 gal), AQ-5200 takes AQ-C2-R (500 gal), Direct Connect AQ-MF-1-R (784 gal), all 6 months.
AquaTru Replacement Filters: Classic, Carafe and Freestanding Filter Sets, Intervals and Cross-Fits
AquaTru Classic filters last 6 months/600 gal (Pre/Carbon), 2 years/1,200 gal (RO), 1 year/600 gal (VOC). Carafe filters are rated 300 gal and do not swap.
Best acid neutralizer filter for low pH well water: calcite vs calcite/Corosex, backwashing vs upflow, by published spec
Calcite treats pH 5.0 to 7.0, a calcite/Corosex blend reaches 4.5, per Clack. Backwashing Fleck 5600SXT vs upflow tanks by tank size, GPM and media.
Best water filter for fluoride removal: which RO systems and pitchers publish a certified fluoride figure, by published spec
iSpring RCC7AK: 97.4% fluoride reduction under NSF/ANSI 58, 75 GPD. Clearly Filtered pitcher: >99.54%, maker-published, not certified. Who should skip.
Best whole house water filter for PFAS: which units carry an NSF/ANSI 53 PFOA/PFOS claim, by published spec
A.O. Smith HomeShield AOS-HS-1200 is the only whole-house unit found with NSF/ANSI 53 PFAS certification: below 4 ng/L for 500,000 gal at 5.7 gpm.
Does reverse osmosis remove PFAS, fluoride, lead, nitrate, arsenic, bacteria, microplastics and sodium? One table, by NSF/ANSI claim
RO removes a contaminant only when its NSF/ANSI 58 or 53 listing names it: lead passes at 5 ppb, PFOA/PFOS at 20 ppt. Bacteria is NSF/ANSI 55 UV, not RO.
EPA drinking water standards table: every MCL, MCLG, action level and secondary standard a home water test reports against
Every EPA MCL in one table: arsenic 0.010 mg/L, nitrate 10, lead action level 0.015 (0.010 from Nov 2027), PFOA and PFOS 4.0 ppt, secondary standards.
How to read a water test report: what ND, MDL, MCL and the units mean, and why a passed report can still taste, smell or stain
A passed report means every MCL was met. Iron 0.3 mg/L, manganese 0.05 and pH 6.5 to 8.5 are unenforced secondary standards a lab may not flag.
Iron filter size calculator: the largest tank your well pump can backwash for Birm, GreensandPlus or Katalox Light
Largest tank = pump GPM divided by the media backwash rate. A 10 GPM pump backwashes a 12-inch Birm tank (9.4 GPM needed) and stalls on 13-inch (11.1 GPM).
Microplastics in tap water: what EPA's draft CCL 6 means, which certification tests for them, and which filters carry it
EPA's draft CCL 6 (April 2026) lists microplastics with no limit. NSF/ANSI 401 is the only test: 85% reduction of 0.5 to 1 micron particles.
NSF/ANSI water filter standards explained: what 42, 53, 58, 401, 55, 44, 177, 372 and 61 each certify, why P473 is withdrawn, and how to check a listing
NSF/ANSI 42 is taste, 53 is health contaminants, 58 is RO at 75% TDS reduction, 55 is UV at 40 mJ/cm², and P473 is withdrawn into 53 and 58.
PUR Pitcher Filter Replacement: PUR Plus PPF951K vs Plain PUR PPF900Z vs the Older CRF-950Z, Which Pitchers Take Each and What the Cross-Fits Claim
PUR Plus PPF951K (99.7% lead reduction at pH 6.5) and plain PPF900Z fit the same 14 PUR pitchers, replaced every 2 months or 40 gallons per PUR.
Reverse osmosis waste water ratio: what the NSF/ANSI 58 efficiency and recovery ratings mean, and where whole-house RO reject water goes
Under-sink RO wastes 4 to 5 gallons per gallon made per APEC. Whole-house RO reject should not go to a septic system, per UMN Extension.
Samsung HAF-QIN/EXP Refrigerator Water Filter: DA97-17376B vs DA97-08006C, Which Fridges Take It and the 6-Month Interval
Samsung lists HAF-QIN/EXP as cartridge DA97-17376B for system DA97-08006C, rated 300 gallons or 6 months, NSF/ANSI 42 and 53 (no 401 on Samsung's page).
TDS meter reading: what the number means, what is too high, and what the pen cannot see
A TDS pen reads conductivity times a factor, not contaminants. EPA's secondary standard is 500 mg/L; NHMRC rates 0 to 600 mg/L good for taste.
Too much water in the water softener brine tank: how much is normal, and the five causes in the order to check them
A brine tank holds about 1 inch over the grid (Fleck) or 2 to 5 inches (GE) by design. Higher means a plugged injector or drain line; check in that order.
Uranium or radon in well water: the limits, and what removes each
EPA's uranium MCL is 30 ug/L, removed by anion exchange or RO. Radon in water has no final MCL, only a 1999 proposal; aeration vents it.
Whirlpool EDR4RXD1 (EveryDrop Filter 4): Which Refrigerators Take It, What It Replaces, and Which Cross-Fits Match
Whirlpool EDR4RXD1 (EveryDrop Filter 4) replaces Maytag UKF8001 and 4396395 per cross-fit makers, rated 300 gallons or 6 months, NSF/ANSI 42 and 372.
ZeroWater Filter Compatibility: Which Pitchers the ZR-017 Fits, When to Change It at TDS 006, and the 2025 Culligan ZeroWater Filter
One ZR-017 filter fits every legacy ZeroWater pitcher; the 2025 Culligan ZeroWater line takes ZEROF01. Both makers say replace at a TDS reading of 006.
Algae, slime or organisms inside a filter housing: what the growth is, and what stops it
Green growth in a clear housing is algae on light: fit an opaque sump. Rusty or oily slime is iron bacteria: shock chlorinate at 200 ppm max per MDH.
Arsenic in well water: what the lab result means, why arsenic III or arsenic V decides the treatment, and what a softener cannot do
EPA's arsenic MCL is 10 µg/L (0.010 mg/L). Arsenic V leaves via RO, anion exchange or adsorptive media; arsenic III needs oxidation first.
Best faucet mount water filter: NSF/ANSI 42, 53 and 401 listings, gallons per cartridge, flow and faucet fit, by published spec
PUR PLUS RF9999: NSF/ANSI 42, 53 and 401 listed, 99.92% Total PFAS, 100 gallons, 0.52 gpm. ZeroWater ExtremeLife: 400 gallons, PFOA/PFOS only, no lead line.
Best portable RV water softener: 16,000 and 8,000 grain exchange units, sized from a hardness number, by published spec
On The Go OTG4-VM-DBLSOFT and Glacier Fresh at 16,000 grains cover most hookups; divide grains by hardness in gpg for gallons between regenerations.
Best RV inline water filter and hose filter: micron rating, media, NSF listing, service life and hose fittings, by published spec
No RV inline filter page read lists NSF/ANSI 53. The one maker with published figures rates 5 micron nominal, 1 to 4 months, on a 3/4 in hose thread.
Best water softener for city water: the Amazon-buyable units compared on resin volume, service flow, NSF/ANSI 44 wording and warranty, by published spec
AFWFilters Fleck 5600SXT 48K: 1.5 cu ft of 10% crosslink resin, 6.5 gpm, 5-year valve and 10-year tank warranty. Six in-stock Amazon units compared on maker figures.
Best whole house water filter for well water: cartridge systems compared on iron and manganese rating, micron, GPM and capacity
Pick: iSpring WGB32BM, rated to 3.0 mg/L iron and 1.0 mg/L manganese, 15 GPM, 100,000 gallons. Above 10 mg/L combined, a cartridge is the wrong tool.
Fleck 5600SXT Parts and Part Numbers: Every Pentair Number From the Service Manual, and Which Ones a Homeowner Actually Replaces
Fleck 5600SXT parts by Pentair number: seal kit 60125, bypass 60049, turbine meter 60626, injector 10913-x by tank size, per service manual 42684.
Fleck 5600SXT settings: what to enter for capacity, hardness and iron, and which entries waste salt
Capacity = resin cu ft x grains per cu ft (1.0 cu ft at 8 lb = 22,000 grains), hardness in tested gpg, and metered regeneration, not a timer.
Frigidaire ULTRAWF PureSource Ultra Filter: Which Refrigerators Take It, How It Differs from WF3CB, EPTWFU01 and FPPWFU01, and Which Cross-Fits Are NSF Listed
Frigidaire ULTRAWF fits the PureSource Ultra push-twist housing. Cross-fits list NSF/ANSI 42 at 300 gal, 0.5 gpm. Not a WF3CB or EPTWFU01 fit.
GE MWF Refrigerator Water Filter: Which GE and Hotpoint Refrigerators Take It, What GE Publishes, and Which Cross-Fits NSF Actually Lists
GE MWF twist-in cartridge: which GE and Hotpoint fridges take it, and which cross-fits NSF lists to 42, 53 and 401 at 300 gallons and 0.5 gpm.
GE Whole House Water Filter Replacement: Which FX Cartridge Fits the GXWH40L, GXWH35F and GXWH04F Housings
GE GXWH40L and GXWH35F take the 10 x 4.5 in FXHSC or FXHTC every 3 months; GXWH04F shares the WS03X10038 O-ring. Which FX cartridge fits which housing.
GE XWF and XWFE Refrigerator Water Filters: Which GE Refrigerators Take Each, the 6 Month Interval, the Chip in the XWFE, and Which Cross-Fits Carry One
GE XWFE replaces the XWF and fits any GE fridge that names either; GE says 6 months, no gallon figure. Which cross-fits carry the chip.
Kenmore 9081, 9083 and 9930 Refrigerator Filter: Which EveryDrop Filter Each Number Crosses To, and What Else Fits
Kenmore 46-9081 is EveryDrop Filter 1 (EDR1RXD1), 46-9083 is Filter 3 (EDR3RXD1), 200 gallons or 6 months each; 46-9930 lists under Filter 1.
PUR Faucet Filter Replacement: RF9999 vs RF3375, Which Mounts Take Each Cartridge, and the Cross-Fits That Claim to Fit
PUR's sheet gives RF9999 and RF3375 one rating: 100 gallons, 0.52 gpm, NSF/ANSI 42, 53 and 401, and one fit list of 24 mounts from FM2500V to PFM400H.
Reverse Osmosis Membrane Replacement Cross-Reference: Which 1812 Membranes Fit an Under-Sink System at 50, 75 and 100 GPD
A 1812 RO membrane is 11.74 x 1.75 in per DuPont's data sheet: FilmTec TW30-1812, iSpring MC7 and MC1, APEC MEM-ES-50 and Express Water ROM all fit.
Reverse Osmosis Storage Tank Replacement: Which 1/4 in Tank Fits, Usable Gallons and the Factory Precharge by Maker
Standard RO tanks: 1/4 in NPT, 4 gal nominal, about 3.2 gal usable, factory precharge 5 to 10 psi by maker. Which tank fits, and how to swap it.
Water softener not using salt: the salt bridge, mushing, injector and float checks behind a brine tank that never drops
A salt bridge is the usual cause. Pentair's 5600SXT manual says keep the tank below half-full, break the crust with a broom handle and wait 2 hours.
Water softener resin replacement: standard 8% crosslink vs. ResinTech's highly crosslinked CNS10, how many cubic feet, and what each maker actually publishes
Refill 1 cu ft of 8% crosslink cation resin per rated cubic foot (ResinTech CG8, Purolite C100E). ResinTech's highly crosslinked CNS10 only behind a chlorine feed.
Whirlpool EDR3RXD1 (EveryDrop Filter 3): Which Refrigerators Take It, What It Replaces, and Which Cross-Fits Match
Whirlpool EDR3RXD1 (EveryDrop Filter 3) replaces P1WB2 and, per cross-fit makers, 4396841: 200 gallons or 6 months, 73 contaminants per Whirlpool.
10 Inch Water Filter Cartridge Compatibility: Which 10 x 2.5 in Cartridges Fit a Standard Housing
A standard 10 in housing takes any 10 x 2.5 in DOE cartridge: Pentek P5 sediment at 2.38 x 9.88 in, CBC-10 carbon block at 2.88 x 9.75 in, on a #237 O-ring.
20 Inch Big Blue Cartridge Compatibility: Which 20 x 4.5 in Filters Fit Any Housing
Every 20 in Big Blue housing takes a 20 x 4.5 in cartridge: Pentek DGD at 4.50 in, EP-20BB at 4.63 in, 1 to 25 micron. Carbon block runs fatter than sediment media.
APEC ROES-50 Replacement Filters: Which Cartridges Fit the ROES-50 and ROES-PH75, and What Cross-Fits
The APEC ROES-50 takes FILTER-SET-ES (stages 1-3, every 6-12 months) and a MEM-ES-50 membrane every 2-4 years. The ROES-PH75 needs the ESPH sets, not the ES ones.
Aquasana Rhino EQ-1000 Replacement Filters: Pre-Filter, Post-Filter, Tank and Cross-Fits
The Aquasana Rhino EQ-1000 takes an EQ-304 pre-filter every 2 months, an EQ-PFC.35 post-filter every 6 months and an EQ-1000R tank at 1,000,000 gallons or 10 years.
Best countertop reverse osmosis system for renters: NSF/ANSI 58, GPD, drain ratio, tank size and filter cost, by published spec
Waterdrop M6SL is the pick: NSF/ANSI 58 and 372 on its page, 75 GPD, 3:1 pure to drain, $69.99 filter per 1,100 gallons. Six units on published spec.
Best shower head filter for chlorine and hard water: no brand here is in NSF's 177 listing, and only one names the standard at all
NSF/ANSI 177 covers free chlorine only. No brand here is in NSF's listing. Sprite's own sheet names the standard; Culligan names only a certifier.
Best spin-down sediment filter for well water: screen micron and mesh, port size, GPM, pressure and auto-flush, by published spec
iSpring WSP-50: 50 micron stainless mesh, 20 GPM, 25 to 80 psi. Auto-flush: WSP50ARB, 25 GPM. High flow: Rusco 1-1/2 in, 18 to 100 GPM, 150 psi.
Best tankless reverse osmosis system: pure-to-drain ratio, GPD, NSF/ANSI 58 vs 372 and filter cost, by published spec
Waterdrop X12 leads at 1,200 GPD and 3:1 pure to drain, NSF/ANSI 58 and 372 listed. Waterdrop G3P600 is the right-sized pick at 600 GPD and 2:1.
Best under-sink reverse osmosis system: tank vs tankless, GPD, drain ratio and NSF/ANSI 58, by published spec
Tankless: Waterdrop G3P800, 800 GPD, 3:1 pure to drain, NSF/ANSI 58 and 372. Tanked: iSpring RCC7AK, 75 GPD, NSF/ANSI 58, alkaline stage. Yearly filter cost.
Best under-sink water filter without reverse osmosis: direct-connect carbon units compared on NSF/ANSI 42, 53 and 401, capacity and flow
CuZn UC-200: 50,000 gallons or 5 years, NSF/ANSI 42 and 372 listed. Aquasana Claryum Max Flow: NSF/ANSI 42, 53 and 401, 99.7% PFOA/PFOS, 800 gallons.
Best UV water purifier for well water: Viqua VH410 vs D4 vs HQUA vs Bluonics, by published dose and NSF/ANSI 55 class
Viqua VH410: 18 GPM at 30 mJ/cm2, 14 GPM at 40 mJ/cm2, 9,000-hour lamp. No unit here is NSF/ANSI 55 Class A; the VH410-V is Class B at 14 GPM.
Best water filter pitcher for lead and PFAS: which filters are certified to NSF/ANSI 42, 53 and 401, by whom, and at what cost per gallon
Brita Elite is the only pitcher filter here WQA certified to NSF/ANSI 42, 53 and 401: 120 gallons a filter, about $0.17 a gallon. Rivals are tested, not certified.
Best water softener for well water: clear-water iron rating, grain capacity and NSF/ANSI 44, by published spec
AFWFilters Iron Pro 2 64K: the only Amazon-sold softener with a printed iron ceiling, 6 ppm, 2 cu ft fine mesh resin, 10 gpm. Above 5 ppm an iron filter goes first.
Best water softener salt: pellets vs solar crystals vs potassium chloride, compared on published purity, insolubles and bridging risk
Pellets with an anti-bridging additive at 99.65% to 99.8% published purity are the default; potassium chloride needs 10 to 15% more product per regeneration.
Best water test kit for well and city water: strips vs mail-in certified lab, by published spec
A mail-in certified lab kit (Tap Score Essential, 54 analytes, 5 business days) beats strips: no strip reads a coliform count, lead at 15 ppb or PFAS.
Best whole-house water filter for city water: chlorine vs chloramine, tank vs cartridge, by published spec
Chlorinated city water: Pentair Pelican PC600 (NSF/ANSI 42 and 61, 662,400 gal, 8 gpm) or Aquasana EQ-1000 (1,000,000 gal). Over 8 GPM: iSpring WGB32B, 15 GPM.
Brita Filter Compatibility: Which Pitchers Take the Standard, Elite and Stream Filter, and Which Ones Interchange
Brita Standard (OB03) and Elite (OB06) fit every Brita pitcher except Stream and interchange: 40 gal vs 120 gal. Stream (OB05) fits only 3 models.
Chlorine or chloramine in city water: how to find out, and which carbon removes which
EPA gives chlorine and chloramine the same 4.0 mg/L limit; only removal differs. Read the CCR, run a free-and-total strip, then pick the carbon.
Coliform-positive well water: what total coliform vs E. coli means, and what fixes each
A coliform-positive well test means the sanitary barrier failed: shock chlorinate at up to 200 ppm, retest in 2 to 4 weeks, then UV at 40 mJ/cm2 if it returns.
Culligan HF-360 and WH-HD200-C Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives
The Culligan HF-360 takes 10 x 2.5 in cartridges (CW-MF, CW-F, P5); the WH-HD200-C takes 10 x 4.5 in (R50-BBSA, CW5-BBS, RFC-BBSA), 8,000 to 24,000 gallons each.
Fluoride in tap water: how to find your level after the 2025 state bans, and which filters reduce it
Utah and Florida stopped adding fluoride in 2025; EPA's MCL stays 4.0 mg/L. How to read your CCR, and which filter classes reduce fluoride, and which do not.
GE RPWFE Refrigerator Water Filter: Which Refrigerators Take It, the 170 Gallon Interval, the RFID Chip, and Which Cross-Fits Carry One
GE RPWFE: 170 gallons or 6 months, NSF/ANSI 42 and 53 per GE's data sheet, plus the RFID chip the RPWF lacks. Which cross-fits carry a chip.
iSpring RCC7 Replacement Filters: Which Cartridge Fits Each Stage of the RCC7, RCC7AK and RCC7AK-UV
iSpring RCC7 stages take FP15, FG15, FC15 (10 in, 5 micron) every 6 months, the MC7 membrane every 2-3 years, FT15 yearly. F7-GAC fits RCC7, F9K fits RCC7AK.
Lead in tap water: how to tell if you have a lead service line, and which filter class removes it
EPA's lead action level is 15 ppb, dropping to 10 ppb on 1 November 2027. Three checks find a lead service line; NSF/ANSI 53 or 58 filters pass at 5 ppb.
LG LT1000P Refrigerator Water Filter: Which Part Numbers Fit, the 200 Gallon Interval, and What Differs From the LT1000PC and LT700P
LG LT1000P (ADQ74793501) is rated 200 gallons or 6 months and listed to NSF/ANSI 42, 53 and 401 by LG. It does not fit LT700P refrigerators.
LG LT700P Refrigerator Water Filter: Part Numbers, What Fits, Cross-Fit Alternatives and Why It Is Not an LT1000P
LG LT700P (ADQ36006101) is rated 200 gallons or 6 months, NSF/ANSI 42 and 53 per LG's page, and does not fit an LT1000P (ADQ74793501) housing.
Micron rating picker: which sediment filter micron for grit, haze, cysts, RO or UV
Coarse to fine: a 700 to 15 micron screen, then a 5 micron cartridge (NDSU: 10 to 15 micron for a drilled well, 2 for a dug well), absolute 1 micron for cysts.
Nitrate in well water: the 10 mg/L limit, where it comes from, and what removes it
Nitrate in well water above EPA's MCL of 10 mg/L as N (45 mg/L as nitrate) needs RO, anion exchange or distillation. Boiling and softeners remove none.
PFAS in tap water: what the 4.0 ppt limit means, and which filter certification counts
EPA's 2024 rule sets PFOA and PFOS at 4.0 ppt. Only filters certified to NSF/ANSI 53 or 58 with a PFOA/PFOS claim are tested for it, to a 20 ppt protocol.
Reverse osmosis GPD and tank size calculator: real output from pressure, temperature and people
Effective GPD = rated GPD x (psi / 60) x (1 + 0.015 x (F - 77)). A 75 GPD unit at 50 psi, 60 F makes about 47 GPD from a 3.2 gal tank. Calculator.
Reverse osmosis remineralization: what the low TDS and pH readings mean, and whether a mineral cartridge is needed
RO strips 90 to 99% of dissolved solids per APEC. EPA's pH 6.5 to 8.5 and TDS 500 mg/L are ceilings with no mineral floor, so remineralize for taste.
Salt-free water conditioner vs softener: what each changes, what it certifies, and which fits your water
An NSF/ANSI 44 softener drops hardness under 1 gpg. A TAC salt-free conditioner leaves it unchanged; its only pass mark is IAPMO Z601's 70% less-scale test.
Samsung DA29-00020B Refrigerator Water Filter: Which Fridges Take It, the 300-Gallon Interval and Which Cross-Fits Match
Samsung rates the DA29-00020B (HAF-CIN/EXP) at 300 gallons or 6 months and lists it to NSF/ANSI 42 and 53; fits RF22 to RF28 French-door models.
Sediment and turbidity in well water: what the cloudiness is, and which filter stops it
Cloudy well water above 5 NTU shows in a glass (NDSU); UV needs under 1 NTU (VIQUA). Sand: a spin-down screen. Silt and clay: a 5 micron pleated cartridge.
Softener resin volume to grain capacity calculator: cubic feet, salt dose and tank size
Usable grains = resin cu ft x grains per cu ft at the salt dose. 1.0 cu ft of 8% resin gives 20,000 grains at 6 lb, 24,000 at 10 lb. Calculator and tank table.
UV water purifier size calculator: GPM at NSF/ANSI 55 Class A dose from bathrooms
Peak gpm = bathrooms x 2.5 + 2.2; a 2-bath house pulls 7.2 gpm. Size to the 40 mJ/cm2 Class A rating: a VIQUA VH410 sold as 18 GPM is 14 gpm at that dose.
Viqua UV Lamp Cross-Reference: S330RL, S463RL, S810RL, 602805, 602806 and Their Sleeves
Viqua S463RL fits the S5Q-PA, S330RL the S2Q-PA, 602805 the D4, 602806 the E4. Each lamp is rated 9,000 hours, changed yearly; sleeve cleaned every 12 months.
Water hardness unit converter: gpg, mg/L, ppm, dH, fH, Clark and mmol/L
1 gpg = 17.118 mg/L as CaCO3, 1 dH = 17.848, 1 fH = 10, 1 Clark = 14.254, 1 mmol/L = 100.09. Convert any hardness unit to the others and read the USGS band.
Water softener salt usage calculator: pounds per regeneration and bags per year
Salt per regeneration = resin cu ft x dose (6, 10 or 15 lb/cu ft). A 1 cu ft unit at 10 lb, 4 people, 10 gpg uses about 406 lb a year: ten 40 lb bags.
Waterdrop 10UA, 15UA and 10UB Replacement Filters: Which Cartridge Fits, the Gallon and Month Interval, and Why the UF and TSA Take Different Parts
Waterdrop 10UA and 10UB take the WD-RF10 (11,000 gallons or 12 months); the 15UA takes the WD-RF15 (19,000 gallons or 24 months). UF housings differ.
Waterdrop G3P800 Replacement Filters: Which Parts Fit, and What the G3 and G3P600 Share
The Waterdrop G3P800 takes the WD-G3-N1CF (6 months), WD-G3-N3CB (12 months) and WD-G3P800-N2RO membrane (24 months). Only the membrane differs across the G3 line.
Whirlpool EDR1RXD1 (EveryDrop Filter 1): Which Refrigerators Take It, What It Replaces, and Which Cross-Fits Match
Whirlpool EDR1RXD1 (EveryDrop Filter 1) replaces W10295370A: 200 gallons or 6 months, NSF/ANSI 42, 53 and 401 per Whirlpool, and the cross-fits.
Whirlpool WHES30 and WHES40 Parts: Nozzle and Venturi, Seal Kit, Brine Valve, Error Codes
Whirlpool WHES30/WHES40 parts by number: seal kit 7129716, nozzle and venturi 7398705 (WHES40) or 7398674 (WHES30), brine valve 7381180, and what Err1 to Err5 mean.
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.