No filter needed
Only the hot water smells
Often the heater's magnesium anode rod. An aluminum anode is the simple fix.6
Sulfur smell guide · Updated Oct 31, 2026
Rotten-egg smell at every tap? One tank for sulfur up to 8 ppm
No lab report needed to start: SpringWell tests your water before the system ships, and refunds the system if it doesn't fit.
We may earn a commission if you buy through our links. It doesn't change the pick.
Our pick for sulfur smell up to 8 ppm
SpringWell WS1
$2,100 brand list price $2,625 Price checked Oct 31, 2026
- H₂S ≤ 8
- Iron ≤ 7
- Mn ≤ 1 ppm1
Check price at SpringWell(paid link)
Water test $134.25, added at checkout, not refundable. Free shipping to the lower 48.1, 2
- Lifetime limited warranty1, 3 Valves and fittings; mineral tanks 14″+ 10 yrs; head 5–7 yrs Valves & fittings; tanks 14″+ 10 yrs
- Free shipping to the lower 482 Continental US only
- DIY install keeps the warranty4 Or hire a plumber: the warranty applies either way
- Owned by Fortune Brands5 Moen's parent company, since February 2024
First: hot water only, or every tap?
Smell the cold tap, then the hot. It tells you whether you need a filter.
In the well water
Hot and cold water smell
The gas is in the well water; its level decides the fix.6 What works at your level
What else do you see? Tap all that apply.
Tick what you see. Nothing is sent anywhere.
That's what the WS is built for: H₂S up to 8, iron up to 7, manganese up to 1 ppm
No report needed: SpringWell tests your water before it ships.1, 2
Chlorinate the well first, then re-test
Slime points to iron or sulfur bacteria. A filter doesn't control them inside the well, so shock-chlorinate first and test again once the chlorine is gone.8, 23 Then check the new numbers against a filter.
An oxidizing filter isn't the answer for these signs
Treat the cause below first. The filter selector shows what fits once you have test results.
Iron
Orange stains and a metallic taste are the classic signs. Water that leaves the tap clear and turns orange on standing carries dissolved iron.7 More
Manganese
Black or brown-black stains and a bitter taste point to manganese, often together with iron.7 More
Hydrogen sulfide
A rotten-egg smell at every tap comes from hydrogen sulfide gas in the water itself.6 More
Hot-water smell: probably your water heater
When only the hot water smells, the cause is often the heater's magnesium anode rod. An aluminum anode is the simple fix; the smell needs no filter.6 More
How ordering works
No lab report needed. The test is part of the order.
-
Order with the $134.25 test
SpringWell adds its lab test to the same checkout.1
-
SpringWell reviews your results
The order waits for the lab results. If changes are needed, SpringWell contacts you.1, 2
-
It ships, or the system is refunded
If it doesn't fit your water, the order is cancelled and the system refunded. The test isn't.1
The filter we'd look at first
SpringWell WS1 / WS4
Best for: sulfur smell at every tap
- H₂S (sulfur)
- 8 ppm
- iron
- 7 ppm
- manganese
- 1 ppm
Stated maximums, pH 6.5 or higher1
$2,100 brand list price $2,625
+ $134.25 water test, required · WS4 $2,5201
WS1 sale price, checked Oct 31, 2026. Check the current price.
Check price at SpringWell(paid link)
- Water tested before it ships; system refunded if it doesn't fit (the $134.25 test isn't)
- Lifetime limited warranty on valves and fittings; mineral tanks 14″+ 10 years; electronic head 5–7 years (registered owner, water within spec)
- Returns within 6 months if uninstalled, 10% restocking fee
- Free shipping to the lower 48
Why it fits
- One tank for sulfur, iron and manganese, within the stated limits
- Air injection: no chlorine to buy, no cartridges, self-cleaning backwash
- WS1 for 1–4 bathrooms, WS4 for 4+
Needs an outlet that isn't on a switch, and a drain line.14
How we chose: 4 checks, no lab testing by us
How it works: air, then a filter bed
No chlorine to buy and no cartridges: oxidation, then filtration, then a self-cleaning backwash.1, 6, 14
- Air pocket. Oxygen at the top of the tank turns hydrogen sulfide, and any iron or manganese, into particles.
- Media bed. The particles get trapped in the bed; the water leaves the bottom of the tank.
- Backwash. On a schedule, the tank flushes the particles to the drain and refreshes the air.
Skip the WS if…
Every limit, with what to do instead.
- H₂S above 8 ppm Chlorination and a filter (about 20 minutes of contact)6
- Sulfur or iron bacteria Shock-chlorinate the well; if slime returns, chlorination with a filter or professional well cleaning; if coliform returns, NSF/ANSI 55 Class A UV8, 22
- pH below 6.5 Correct the pH first (neutralizer)11, 15
- You need certified performance We found no NSF listing for SpringWell's well systems16
Aquasana's Rhino Well is a KDF and carbon tank plus UV; for iron, Aquasana says you "may need a specialized filter".17 Compare both
Check your numbers
Have a lab report? See whether the WS fits, and which size.
Within SpringWell's stated limits
Your numbers are inside what SpringWell states the WS handles: hydrogen sulfide up to 8, iron up to 7, manganese up to 1 ppm.1 Your pH is inside its 6.5–10 range too. Size: WS1.
pH not entered: the WS needs pH 6.5–10. Check it on your report before you order.
Your report should also show bacteria. The WS doesn't treat bacteria: if coliform is present, fix the source and add disinfection.
Check price at SpringWell(paid link)
Above the WS's stated limits
Above those levels, extension services point to chlorination with about 20 minutes of contact time and a filter after it (for iron, a manganese greensand filter up to about 10 mg/L iron plus manganese), or a custom system from a local water-treatment professional with written NSF or WQA certification.6, 7, 18
What works at your levelCorrect the pH first
The WS needs pH 6.5 or higher. Correct acidic water first, with a calcite neutralizer or a soda-ash feed; otherwise home treatment systems may not work as designed.1, 11
SpringWell states the WS for pH 6.5–10, and your pH is above that.1 Ask the lab to confirm the reading, and talk to a local water-treatment professional before you buy.
Low pH explainedYou may not need an iron filter
No hydrogen sulfide, iron below 0.3 mg/L and manganese below 0.05 mg/L are within EPA's taste-and-odor benchmarks.10 If only the hot water smells, see the anode rod. Check the rest of your report in the full filter selector.
Enter your hydrogen sulfide or iron value. No lab report yet? Start with what you see.
What works at your level: methods by H₂S
Aeration
releases the gas
6
Greensand oxidizing filter
about 2–3
6
SpringWell WS (air injection)
Our pick
manufacturer's stated maximum
1
Chlorination + filter
any level; usually above 6
6
Before you buy
What happens if I order and my water doesn't fit?
If the lab results show the system isn't compatible with your water, SpringWell cancels the order and refunds the system. The $134.25 test isn't refunded. If the results call for changes, its support team contacts you first.
Is hydrogen sulfide a health risk?
EPA has no drinking water standard for hydrogen sulfide itself: it is neither a primary nor a secondary contaminant. Its rotten-egg smell falls under EPA's general odor guideline (3 threshold odor number). You can smell it well below 0.5 mg/L, so the smell usually shows up long before the levels a lab would call high. If you're worried, ask your county or state health department.
Will a carbon filter fix the smell?
Only at low levels: Penn State puts the limit at about 1 mg/L, and UGA Extension warns carbon may fail above 0.3 ppm. Above that, greensand, aeration, or chlorination with a filter work better, and an air-injection filter like the SpringWell WS is rated up to 8 ppm by its maker.
Can I install it myself?
Yes: SpringWell says a DIY install keeps the warranty. You'll cut into the main line, run a drain line for the backwash and plug the head into an outlet that isn't on a switch. Budget for a plumber if that isn't for you.
Can I return it?
Within 6 months, but only unused and uninstalled, with a 10% restocking fee and return shipping at your cost. Installed systems are taken back only if defective. That's why the water test before shipping matters.
Do you get paid for this?
Possibly: links marked paid link can earn us a commission at no cost to you. It's also why we tell you when a $0 fix, the anode rod, is the answer. How we make money.
Answers from SpringWell's pages and policies, EPA and extension guidance.1, 2, 4, 6, 10, 14, 19
Your water gets tested before anything ships
If it doesn't fit, SpringWell cancels and refunds the system. The $134.25 test isn't refunded.1, 2
Our pick for sulfur smell up to 8 ppm
SpringWell WS1
$2,100 brand list price $2,625 Price checked Oct 31, 2026
H₂S ≤ 8 · Iron ≤ 7 · Mn ≤ 1 ppm
Check price at SpringWell(paid link)
Testing first? A certified lab such as UW–Stevens Point charges $153 for a basic panel plus metals21; SpringWell's required $134.25 test is added to the order1.
Order with SpringWell's test (paid link) How to test independently
Sources (24) · checked Oct 31, 2026
- SpringWell: Whole House Well Water Filter System (WS1/WS4) product page (seen 2026-10-31)
- SpringWell: Shipping, returns and refunds (free shipping to the continental US only) (seen 2026-10-31)
- SpringWell: Warranty (seen 2026-10-31)
- SpringWell: ULTRA Well Water Filter + Salt-Free combo (seen 2026-10-31)
- Fortune Brands 10-K: Fortune Brands Innovations, Form 10-K for fiscal 2024 (acquisition of SpringWell, February 29, 2024; Water segment with Moen) (seen 2026-10-31)
- Penn State Extension: Penn State Ext., Hydrogen Sulfide in Water Wells (2024-12-10; checked 2026-10-31)
- Penn State Extension: Penn State Ext., Iron and Manganese in Private Water Systems (2025-05-29; checked 2026-10-31)
- Penn State Extension: Penn State Ext., Iron and Sulfur Bacteria (2024-09-16; checked 2026-10-31)
- Penn State Extension: Penn State Ext., Water Softening (2025-09-08; checked 2026-10-31)
- EPA: EPA, Secondary Drinking Water Standards (2026-05-26; checked 2026-10-31)
- Connecticut DPH: Connecticut DPH, Publication 18: pH-Acidity of Private Wells (May 2009; checked 2026-10-31)
- CDC: CDC, Guidelines for Testing Well Water (2024-07-01; checked 2026-10-31)
- EPA: EPA, Protect Your Home's Water (2026-02-26; checked 2026-10-31)
- SpringWell manual: WS1/WS4 installation instructions (PDF) (seen 2026-10-31)
- UGA Extension: UGA Ext. Bulletin 939, Water Quality and Common Treatments for Private Drinking Water Systems (2026-07-01; checked 2026-10-31)
- NSF listings: NSF certified drinking water treatment units: search for SpringWell (seen 2026-10-31)
- Aquasana FAQ: Rhino Well Water FAQ (seen 2026-10-31)
- Penn State Extension: Penn State Ext., Tips for Buying Water Treatment Equipment (2026-07-01; checked 2026-10-31)
- UGA Extension: UGA Ext. C858-15, Hydrogen Sulfide and Sulfate (reviewed May 2026; checked 2026-10-31)
- Minnesota Dept. of Health: Minnesota Dept. of Health, Home Water Treatment fact sheet (rev. 2024-03-29; checked 2026-10-31)
- UW–Stevens Point lab: UW–Stevens Point WEAL, 2026 Analysis Price List (valid to 2026-12-31; checked 2026-10-31)
- Ohio Dept. of Health: Ohio Dept. of Health, UV Light for Continuous Disinfection (rev. July 2011; checked 2026-10-31)
- UGA Extension: UGA Ext. C858-4, Shock Chlorination (2026-04-17; checked 2026-10-31)
- Penn State Extension: Penn State Ext., Testing Your Drinking Water (2025-06-02; checked 2026-10-31)
SpringWell WS1 · $2,100WS1 · $2,100
Price checked Oct 31, 2026 · free shipping, lower 48Checked Oct 31, 2026 · free shipping
View at SpringWell(paid link)