Which treatment fits each problem
A softener for hard water, an oxidizing filter for iron that does not suit a softener, an oxidizing filter or chlorination for sulfur, and reverse osmosis, distillation or ion exchange for nitrate. E. coli always goes to a well pro first.
An iron filter or a softener, picked from an iron test
Orange-brown stains come from iron. Penn State Extension says a softener can take dissolved iron under 5 mg/L when the water is hard and pH is above 6.7. Otherwise an oxidizing filter is the usual choice. A test decides which.
An oxidizing filter for manganese, after a test
Penn State Extension says black specks or stains come from manganese. Test for manganese and iron first. Above EPA's health advisory of 0.3 mg/L, use another water source for infant formula.
An acid neutralizing filter, after a pH test
Penn State Extension says blue-green stains come from corrosive water, generally low pH and low dissolved solids. It is treated with an acid neutralizing filter, soda-ash injection, or new metal plumbing. Test pH and copper first.
A water softener, sized from a hardness test
Penn State Extension says a grayish-white film, scale and poor suds come from calcium and magnesium, and an ion-exchange water softener treats it. A hardness test gives the number a softener is sized from.
A water heater fix, not a well treatment system
Penn State Extension says a smell in hot water only can often be fixed at the water heater, by replacing the anode rod with one of another metal. That may void the heater warranty, so ask the installer first.
An oxidizing filter, or continuous chlorination followed by a carbon filter; a carbon filter alone only for mild cases
Oxidation is the most common treatment for hydrogen sulfide. Penn State Extension says aeration is normally not used above about 2 mg/L, and carbon is used to polish small amounts.
Clean the drain: no treatment system
Penn State Extension says a smell at one sink only can come from bacteria in the drain, not the water. Disinfect the drain first.
Chlorinating the well, done by a pro, with continuous chlorination in severe cases
Penn State Extension links a musty smell and an orange or slimy film in toilet tanks and sinks to iron bacteria. There is no drinking water standard for them. The treatment is chlorinating the well, and continuous chlorination in severe cases.
Test for iron, manganese and pH before any system
Penn State Extension lists a metallic taste with iron, with manganese, and with corrosive water. Each needs a different system, so test first.
Reverse osmosis or distillation at the tap you drink from
Penn State Extension links a salty taste to chloride from bedrock, road salt or drilling brines, treated with reverse osmosis or distillation at single taps. Test chloride and total dissolved solids first so you know the level.
Anion exchange, or reverse osmosis for small amounts
Penn State Extension links a bitter taste, scale and a laxative effect to sulfate from bedrock or mining, treated with anion exchange or, for small amounts, reverse osmosis. Test sulfate and total dissolved solids first.
Treat the well, flush it, and retest
Coliform without E. coli usually responds to treating the well. Retest about a week later. If it comes back, call a pro. Use bottled water until the well tests clean.
No treatment system yet: a local well pro first
E. coli means something is getting into the well. A pro should find the cause before you treat. Use bottled water until the well tests clean.
An E. coli test, or a well pro, before you treat
Coliform alone does not say how serious it is. Ask the lab to test the same sample for E. coli, or call a well pro before you treat. Use bottled water until the well tests clean.
A coliform and E. coli test, before any treatment system
You usually cannot see, smell or taste bacteria in well water, so test for it before you spend money on a system for anything else.
A cartridge (sediment) filter, or a media filter for heavy sediment
Penn State Extension says silt, sediment and clay make water cloudy. A cartridge filter handles less severe cases, and multi-level media filtration handles more severe ones.
Usually no system: a vented well cap, or aeration for high gas levels
White bubbles that clear from the bottom of the glass up are gas or air. Penn State Extension says dissolved gases such as methane or carbon dioxide are handled with a vented well cap above about 7 mg/L and an aeration system above about 28 mg/L.
A bacteria test first: surface water may be getting in
Water that turns cloudy after heavy rain can mean surface water reaches the well. Minnesota Department of Health says coliform in a water test can mean surface contamination got into the water. Test before you pick a filter.
A nitrate test, before any system
Reverse osmosis, distillation and ion exchange reduce nitrate, but test first so you know you need one. Minnesota Department of Health says to test for nitrate when an infant will use the water or a pregnancy is planned.
How the picker works
- Say what is wrong. Stains, a smell, a bad taste, scale, bacteria, cloudy water or nitrate.
- Add the detail. The stain color, where the smell is, or what the water does in a glass. Orange stains point to iron, black to manganese, blue-green to corrosive water, white to hardness.
- Add a lab number if you have one. Iron, manganese, pH, hardness or nitrate decide the system. With no number, the picker tells you what to test first. You usually cannot see, smell or taste bacteria, so test for it too.
- Read the type of treatment. You get one type of treatment, why it fits, the source for the rule, and whether to test first. Hard water also gets a softener size from your household.
- Follow the route. Coliform without E. coli goes to a treatment kit and a retest. E. coli goes to a well pro first. Other problems go to a local installer.
Questions
What treats hard well water?
A water softener, which uses ion exchange to swap calcium and magnesium for sodium or potassium. USGS calls water over 120 mg/L as calcium carbonate hard. Size the softener to your hardness and the number of people in the home.
Can one softener remove iron too?
Sometimes. Penn State Extension says a softener is generally recommended when dissolved iron is under 5 mg/L, hardness is 3 to 20 grains per gallon and pH is above 6.7. Iron that is already orange in the glass is oxidized and fouls the softener resin, so it needs an oxidizing filter instead.
What removes nitrate from well water?
Reverse osmosis, distillation and ion exchange reduce nitrate when they are maintained, according to the Minnesota Department of Agriculture. Boiling makes nitrate more concentrated, and a water softener does not reduce it. Have the well inspected first, and keep babies under six months off water above 10 mg/L even after treatment.
How do I fix the rotten egg smell in well water?
First find where it starts. Penn State Extension says a smell in hot water only is often the water heater's anode rod, and a smell at one sink can be bacteria in the drain. A smell in both hot and cold water points at the well, where oxidation is the most common treatment.
What if my water has E. coli?
Do not treat it yourself first. E. coli means something is getting into the well. A well pro should find the cause. Do not drink the water. Use bottled water until a well pro has fixed it.
Is this a quote?
No. The picker names a type of system and the rule behind it. It does not name a brand or a price. Only an installer who sees your water and your plumbing can size and quote the job.
Go deeper
- Well water test results explained
- Well water treatment by problem
- Iron filters
- E. coli in well water
- Nitrate in well water
- Arsenic in well water
Not sure what is in your water yet? Get a well water test kit, or look up your well first.
Add this picker to your site
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<iframe src="https://www.savemywell.com/embed/well-water-treatment-picker" title="Well water treatment picker" width="100%" height="1000" style="border:0;max-width:640px" loading="lazy"></iframe>
<p style="font-size:13px"><a href="https://www.savemywell.com/tools/well-water-treatment-picker">Tool by Save My Well</a></p>Sources
- Penn State Extension, Iron and Manganese in Private Water Systems
- Penn State Extension, Hydrogen Sulfide (Rotten Egg Odor) in Water Wells
- Penn State Extension, Common Drinking Water Problems and Solutions
- Minnesota Department of Agriculture, Water Testing for Nitrate
- Minnesota Department of Health, Nitrate in Well Water
- U.S. EPA, Secondary Drinking Water Standards: Guidance for Nuisance Chemicals
- USGS Water Science School, Hardness of Water
- Minnesota Department of Health, Bacteria in Well Water
- Penn State Extension, Water Softening
- U.S. EPA, Drinking Water Health Advisory for Manganese
Private wells are not regulated by EPA. These are the benchmarks agencies give owners. The picker names a type of system, not a product or a price.