Hard water from a private well
Size your softener to your water, not a guess
Most well softener problems come from three things: the wrong size, iron fouling the resin, and a hardness setting that ignores the iron. Start with your numbers.
Softener sizing calculator
Use the hardness and iron from your lab report. If your report gives hardness in mg/L, switch the unit.
How hard is your water?
USGS classes water by its calcium carbonate content. Above about 7 grains per gallon, most homes notice scale on fixtures, spotting and soap that won’t lather, and a softener is usually worth it.
Softener guides
All guides →- Do you need a water softener for well water?Not every well needs a softener. How to decide from your hardness and iron numbers, when softening pays off, and what to fix before you buy one.
- Water hardness levelsWater hardness chart in grains per gallon and mg/L, with both the WQA and USGS scales, a conversion table, and how to read hardness on a well test.
- How to size a water softenerThe method our sizing calculator uses: people times daily water use times compensated hardness, over days between regenerations, with worked examples.
- Iron and water softenersWhat a softener can and can't do with iron: ferrous vs ferric iron, resin fouling, manganese, published limits, and when an iron filter must go first.
- Iron filter vs water softenerAn iron filter removes iron, a softener removes hardness. How to tell which one your well test calls for, when you need both, and which goes first.
- Salt-free vs salt water softenersSalt-free conditioners don't remove hardness, and most need iron-free water. When a salt-free unit can work on a well, and when only a salt softener fits.
- Well water filter and softener comboWhen a well needs both an iron filter and a softener: install order, what each tank needs, how to size the pair from your test, and upkeep.
- Water softeners and septic systemsCan softener brine go into a septic system? What university, EPA and industry-funded studies found, who paid for them, and how to protect your tank.
- Sodium in softened waterA salt softener adds about 8 mg/L of sodium for each grain of hardness removed. How to work out your number, who should care, and the alternatives.
- Water softener settingsHow to set a softener on well water: the hardness number to enter, the iron allowance, salt dose, regeneration time, reserve and day override.
- How to clean iron out of softener resinSigns your softener resin is iron-fouled, how resin cleaners and brine tank cleaning work, when resin needs replacing, and how to stop iron coming back.
- Water softeners for tanninsA standard softener won't remove tannins. How to tell tannins from iron, how anion exchange tannin units work, and what to check before buying one.
- What a water softener costs on a wellTypical water softener price ranges as of 2026, how to work out yearly salt and water costs from your hardness, and what can raise or cut the total.
Reviews
Other well water problems, such as sulfur smell, bacteria, low pH or nitrate? See Well Water Filter Systems.
Common questions
Do I need a water softener for well water?
Only if your water is hard. Above about 7 grains per gallon (120 mg/L) most homes see scale, spots and soap scum, and a softener is usually worth it. Below about 3.5 gpg a softener is rarely worth it.
What size water softener do I need?
Multiply the number of people by about 75 gallons a day and by your hardness in grains per gallon to get grains per day. Multiply that by the days between regenerations (often 7) and pick a softener with at least that capacity. Add about 4 gpg to the hardness for each 1 mg/L of iron.
Can a water softener remove iron from well water?
A softener can remove small amounts of dissolved (clear-water) iron. Extension guidance puts the practical limit at a few mg/L under ideal conditions, but iron slowly fouls the resin, so above about 1 mg/L, or if the water comes out orange, an iron filter ahead of the softener is the safer setup.
Is a softener safe for my septic system?
Most studies and extension services find that a properly set softener does not harm a working septic system. The main thing is to avoid regenerating more often than needed, which sends extra water and salt to the tank.