# OwnerSpec

> Independent, numbers-first specs, sizing and part-compatibility answers for the equipment in your home.

The specs an owner actually needs. OwnerSpec is an independent publisher: it sells, installs and services nothing, and every technical figure is cited to a regulation, a published standard, or the manufacturer's own documentation.

Full text of every page: https://ownerspec.com/llms-full.txt
Machine-readable sitemap: https://ownerspec.com/sitemap.xml
Every page is also available as Markdown: append `index.md` to any URL, or send `Accept: text/markdown`.
MCP server (no authentication, Streamable HTTP): https://ownerspec.com/mcp , documented at https://ownerspec.com/mcp-server/
Search index (JSON, one record per page with quick answer, FAQ, sources and picks): https://ownerspec.com/index.json

## How to cite this site

Cite the canonical URL of the specific page (the public HTML page), not the homepage, not the
Markdown twin and not the MCP endpoint. Every article carries, directly under its short
answer, a fact sheet: the answer with its number, the formula or compatibility basis, the
inputs, the assumptions, the method, the primary source (typed: government, standards body,
extension service, manufacturer document, research), the "facts verified" date and the
canonical URL. Quote the figure together with the source the page names for it, and pass on
the facts-verified date. Dates below are "facts verified" where the page has one.

## 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.

### Calculators

- [Micron rating picker: which sediment filter micron for grit, haze, cysts, RO or UV](https://ownerspec.com/water/calculators/micron-rating-picker/): 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. (verified 2026-09-12)
- [Reverse osmosis GPD and tank size calculator: real output from pressure, temperature and people](https://ownerspec.com/water/calculators/reverse-osmosis-gpd-tank-size-calculator/): 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. (verified 2026-09-12)
- [Softener resin volume to grain capacity calculator: cubic feet, salt dose and tank size](https://ownerspec.com/water/calculators/softener-resin-volume-grain-capacity-calculator/): 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. (verified 2026-09-12)
- [UV water purifier size calculator: GPM at NSF/ANSI 55 Class A dose from bathrooms](https://ownerspec.com/water/calculators/uv-water-purifier-size-calculator/): 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. (verified 2026-09-12)
- [Water hardness unit converter: gpg, mg/L, ppm, dH, fH, Clark and mmol/L](https://ownerspec.com/water/calculators/water-hardness-unit-converter/): 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. (verified 2026-09-12)
- [Water softener salt usage calculator: pounds per regeneration and bags per year](https://ownerspec.com/water/calculators/water-softener-salt-usage-calculator/): 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. (verified 2026-09-12)
- [Water softener size calculator: grain capacity from people, hardness and iron](https://ownerspec.com/water/calculators/water-softener-size-calculator/): 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. (verified 2026-09-11)
- [Whole-house filter flow rate calculator: GPM from fixtures and bathrooms](https://ownerspec.com/water/calculators/whole-house-filter-flow-rate-calculator/): 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. (verified 2026-09-11)

### Guides

- [Chlorine or chloramine in city water: how to find out, and which carbon removes which](https://ownerspec.com/water/guides/chlorine-chloramine-city-water/): 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. (verified 2026-09-12)
- [Coliform-positive well water: what total coliform vs E. coli means, and what fixes each](https://ownerspec.com/water/guides/coliform-positive-well-water/): 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. (verified 2026-09-12)
- [Fluoride in tap water: how to find your level after the 2025 state bans, and which filters reduce it](https://ownerspec.com/water/guides/fluoride-in-tap-water-remove/): 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. (verified 2026-09-12)
- [Lead in tap water: how to tell if you have a lead service line, and which filter class removes it](https://ownerspec.com/water/guides/lead-in-tap-water-service-line/): 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. (verified 2026-09-12)
- [Nitrate in well water: the 10 mg/L limit, where it comes from, and what removes it](https://ownerspec.com/water/guides/nitrate-in-well-water/): 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. (verified 2026-09-12)
- [PFAS in tap water: what the 4.0 ppt limit means, and which filter certification counts](https://ownerspec.com/water/guides/pfas-in-tap-water-what-filter/): 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. (verified 2026-09-12)
- [Salt-free water conditioner vs softener: what each changes, what it certifies, and which fits your water](https://ownerspec.com/water/guides/salt-free-water-conditioner-vs-softener/): 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. (verified 2026-09-12)
- [Sediment and turbidity in well water: what the cloudiness is, and which filter stops it](https://ownerspec.com/water/guides/sediment-turbidity-well-water/): 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. (verified 2026-09-12)
- [Black stains from well water: how much manganese that is and what removes it](https://ownerspec.com/water/guides/manganese-black-stains-well-water/): 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. (verified 2026-09-11)
- [Blue-green stains and pinhole leaks: low pH well water and what neutralizes it](https://ownerspec.com/water/guides/blue-green-stains-low-ph-well-water/): 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. (verified 2026-09-11)
- [How to shock chlorinate a well: chlorine amount, contact time, and when it is the wrong fix](https://ownerspec.com/water/guides/shock-chlorinate-a-well/): 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. (verified 2026-09-11)
- [Iron in well water: how much is behind the rust stains, and what treats it](https://ownerspec.com/water/guides/iron-in-well-water/): 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. (verified 2026-09-11)
- [Rotten egg smell in well water: hydrogen sulfide levels and what removes it](https://ownerspec.com/water/guides/rotten-egg-smell-well-water/): 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. (verified 2026-09-11)
- [Tea-colored well water: tannins, how to tell them from iron, and what removes them](https://ownerspec.com/water/guides/tannins-tea-colored-well-water/): 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. (verified 2026-09-11)
- [What to test well water for: the annual panel, the units, and what each result decides](https://ownerspec.com/water/guides/well-water-test-panel/): 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. (verified 2026-09-11)
- [White Scale on Faucets and Kettles: How Hard Your Water Is and What Fixes It](https://ownerspec.com/water/guides/hard-water-white-scale/): 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. (verified 2026-09-11)

### Parts

- [20 Inch Big Blue Cartridge Compatibility: Which 20 x 4.5 in Filters Fit Any Housing](https://ownerspec.com/water/parts/20-inch-big-blue-cartridge-compatibility/): 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. (verified 2026-09-12)
- [APEC ROES-50 Replacement Filters: Which Cartridges Fit the ROES-50 and ROES-PH75, and What Cross-Fits](https://ownerspec.com/water/parts/apec-roes-50-replacement-filters/): 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. (verified 2026-09-12)
- [Aquasana Rhino EQ-1000 Replacement Filters: Pre-Filter, Post-Filter, Tank and Cross-Fits](https://ownerspec.com/water/parts/aquasana-rhino-eq-1000-replacement-filters/): 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. (verified 2026-09-12)
- [Culligan HF-360 and WH-HD200-C Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives](https://ownerspec.com/water/parts/culligan-hf-360-wh-hd200-replacement-filters/): 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. (verified 2026-09-12)
- [iSpring RCC7 Replacement Filters: Which Cartridge Fits Each Stage of the RCC7, RCC7AK and RCC7AK-UV](https://ownerspec.com/water/parts/ispring-rcc7-replacement-filters/): 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. (verified 2026-09-12)
- [Viqua UV Lamp Cross-Reference: S330RL, S463RL, S810RL, 602805, 602806 and Their Sleeves](https://ownerspec.com/water/parts/viqua-uv-lamp-cross-reference/): 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. (verified 2026-09-12)
- [Waterdrop G3P800 Replacement Filters: Which Parts Fit, and What the G3 and G3P600 Share](https://ownerspec.com/water/parts/waterdrop-g3-g3p800-replacement-filters/): 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. (verified 2026-09-12)
- [Whirlpool WHES30 and WHES40 Parts: Nozzle and Venturi, Seal Kit, Brine Valve, Error Codes](https://ownerspec.com/water/parts/whirlpool-whes30-whes40-parts/): 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. (verified 2026-09-12)
- [Express Water WH300SCKS Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives](https://ownerspec.com/water/parts/express-water-wh300scks-replacement-filters/): Express Water WH300SCKS takes FLTWH2045S1, FLTWH2045K and FLTWH2045C1 (set FLTWH2045CKS1), 4.5 x 20 in, changed every 6-12 months or 100,000 gallons. (verified 2026-09-11)
- [iSpring WGB32B Replacement Filters: Which Cartridges Fit, and Cross-Fit Alternatives](https://ownerspec.com/water/parts/ispring-wgb32b-replacement-filters/): 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. (verified 2026-09-11)

### Reviews

- [Best under-sink reverse osmosis system: tank vs tankless, GPD, drain ratio and NSF/ANSI 58, by published spec](https://ownerspec.com/water/reviews/best-under-sink-reverse-osmosis-system/): 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. (verified 2026-09-12)
- [Best UV water purifier for well water: Viqua VH410 vs D4 vs HQUA vs Bluonics, by published dose and NSF/ANSI 55 class](https://ownerspec.com/water/reviews/best-uv-water-purifier-well-water/): 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. (verified 2026-09-12)
- [Best water softener for well water: clear-water iron rating, grain capacity and NSF/ANSI 44, by published spec](https://ownerspec.com/water/reviews/best-water-softener-for-well-water/): Whirlpool WHES40: 40,000 grains, NSF/ANSI 44, rated 10 ppm clear-water iron, the highest published. GE GXSH40V 8 ppm. Above 5 ppm an iron filter goes first. (verified 2026-09-12)
- [Best water test kit for well and city water: strips vs mail-in certified lab, by published spec](https://ownerspec.com/water/reviews/best-water-test-kit-well-and-city/): 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. (verified 2026-09-12)
- [Best whole-house water filter for city water: chlorine vs chloramine, tank vs cartridge, by published spec](https://ownerspec.com/water/reviews/best-whole-house-water-filter-city-water/): 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. (verified 2026-09-12)
- [Best iron filter for well water: air injection vs manganese greensand vs Birm, by published spec](https://ownerspec.com/water/reviews/best-iron-filter-for-well-water/): 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. (verified 2026-09-11)
- [Best whole-house sediment filter for well water: spin-down vs cartridge, by published spec](https://ownerspec.com/water/reviews/best-whole-house-sediment-filter-well-water/): 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. (verified 2026-09-11)

## Legal

Privacy, cookies, terms of use, affiliate disclosure and disclaimers for OwnerSpec.
- [Affiliate disclosure](https://ownerspec.com/legal/affiliate-disclosure/): How OwnerSpec makes money, which programmes we take part in, and what that does and does not change about what you read.
- [Cookie policy](https://ownerspec.com/legal/cookies/): Every cookie and storage item OwnerSpec uses, what it does, how long it lasts, and how to refuse or withdraw consent.
- [Disclaimer](https://ownerspec.com/legal/disclaimer/): The limits of the information on OwnerSpec, including health, safety, installation and regulatory limits.
- [Editorial policy](https://ownerspec.com/legal/editorial-policy/): How OwnerSpec decides what to publish, where the numbers come from, how we correct mistakes and how commission is kept out of recommendations.
- [Legal notice](https://ownerspec.com/legal/imprint/): Publisher identification for OwnerSpec.
- [Privacy policy](https://ownerspec.com/legal/privacy/): What data OwnerSpec collects, why, on what legal basis, who receives it, and how to exercise your rights under the GDPR.
- [Terms of use](https://ownerspec.com/legal/terms/): The terms on which OwnerSpec is made available, including liability limits, intellectual property and applicable law.

## Policies

- [Editorial policy](https://ownerspec.com/legal/editorial-policy/): where the numbers come from and what we never do.
- [Affiliate disclosure](https://ownerspec.com/legal/affiliate-disclosure/): how the site is funded.
- [Privacy policy](https://ownerspec.com/legal/privacy/)
- [Terms of use](https://ownerspec.com/legal/terms/): quoting with attribution and a link is permitted.