Hard well water

Best for

Homes with hardness above 7 gpg (120 mg/L), pH of 6.5 or higher, and iron, manganese and sulfur already under control.

Wrong fit

Homes on a low-sodium diet should talk to a doctor first. Wells with oxidized iron, sulfur or low pH need those treated before a softener.

Tradeoff

A softener needs salt, a drain and some sodium in the water. It does not purify water or remove most health contaminants.

What hard water looks like

Hardness is the amount of dissolved calcium and magnesium in your water. Groundwater picks these minerals up as it moves through soil and rock, so well water is often harder than surface water, especially in limestone areas. The signs are familiar:

• White or gray scale on faucets, showerheads and inside kettles.
• Spots and film on dishes and glassware.
• Soap and shampoo that do not lather well, and a soap-scum ring in the tub.
• Shorter life and lower efficiency for water heaters. The USGS says scale from heated hard water can reduce equipment life, raise water heating costs and clog pipes.
• More soap and detergent needed to get hands, hair and laundry clean, as the USGS notes.

Is it a health risk?

No. Penn State Extension says calcium and magnesium have no adverse health effects and are in fact essential nutrients. The USGS notes that hard water can even contribute some calcium and magnesium to the diet. There is no EPA health standard for hardness. The case for softening is about scale, cleaning and appliance life, which makes it a cost decision rather than a safety one.

How to read your hardness number

Labs report hardness in mg/L (or ppm) as calcium carbonate, and softener makers size equipment in grains per gallon. One gpg equals 17.1 mg/L. Penn State’s classification:

The USGS uses similar breaks in mg/L: 0 to 60 soft, 61 to 120 moderately hard, 121 to 180 hard, and more than 180 very hard.

Penn State also recommends an independent lab test rather than relying on a dealer’s free hardness check, so you are not oversold. The guide to testing your well covers what to order, and the test results tool converts units for you.

What level needs treatment

The honest answer for moderately hard water is that you may not need anything.

Treatment options

How a softener works

A salt-based softener is an ion exchange unit. Water passes through a bed of resin beads holding sodium ions. Calcium and magnesium stick to the resin and sodium is released in their place. When the resin is full, the unit regenerates: it rinses the resin with salt brine and sends the hardness minerals to the drain. Penn State notes that demand-controlled models, which regenerate based on water use, waste less salt and water than timed models.

Penn State also points out that not every tap needs soft water. Showers, sinks and laundry are the main targets; toilets, outside spigots and basement sinks can be bypassed.

For well water with hardness above 7 gpg and pH of 6.5 or higher, SpringWell’s salt-based water softener is one option. SpringWell lists the SS1 for 1 to 3 bathrooms (32,000 grains, 11 GPM), the SS4 for 4 to 6 bathrooms (48,000 grains, 13 GPM) and the SS+ for 7 or more bathrooms (20 GPM), all rated for pH 6.5 to 10. The water softener for well water guide covers softeners in more depth, and wellwatersoftener.com has a sizing calculator and more on softener settings.

Sizing a softener

Penn State gives a worked example. A household of four using 75 gallons per person per day, with hardness of 10 gpg, needs to remove 3,000 grains a day (75 × 10 × 4). A softener with 20,000 grains of capacity would then regenerate about every six to seven days. Penn State also notes that all softeners use essentially the same process, so they differ mainly in convenience features, and advises being wary of sales claims that one model will outlast or out-soften another.

Salt-free conditioners

Salt-free systems that use template-assisted crystallization do not remove hardness; they change how the minerals behave so they form less scale. On well water, the bigger issue is their tolerance for other minerals. SpringWell’s own FutureSoft spec lists a maximum of zero for iron, manganese and hydrogen sulfide, and a pH range of 7.0 to 9.5. That rules it out for untreated well water with any of those problems. If your well water has been fully treated for iron, manganese and sulfur and your pH sits in that range, it becomes an option, but it still will not deliver soft water.

Softeners and iron

A softener can remove small amounts of dissolved iron along with hardness. Penn State says this works best when pH is above 6.7, hardness is 3 to 20 gpg and dissolved iron is under 5 mg/L. Iron that has already oxidized, from air in the system or from chlorine, fouls the resin and needs filtering out first. Above those limits, put an iron filter ahead of the softener; see iron in well water. Tea-colored water from tannins needs a different resin; see tannins in well water.

Order of treatment

1. Sediment filter, if there is sand or silt. Penn State notes turbid water can clog softener resin.
2. pH neutralizer, if pH is below 6.5. A calcite neutralizer adds hardness as it raises pH. Connecticut’s health department recommends testing hardness after a neutralizer is installed, and says users may prefer to soften once levels reach 120 to 180 mg/L. See acidic well water.
3. Iron, manganese and sulfur filter.
4. Softener.
5. UV, last, if the well needs disinfection.

Sodium, septic and other trade-offs

• Sodium. Penn State estimates a softener adds about 7.5 mg of sodium per quart for each gpg removed, so water softened from 15 gpg gains roughly 110 mg per quart. Virginia Cooperative Extension advises people on sodium-restricted diets to consult a physician. A bypassed cold tap at the kitchen sink is a common answer.
• Septic and discharge rules. Regeneration sends brine to a drain. Some states restrict this; Connecticut, for example, prohibits regeneration waste discharges to a septic system. Check your state and county rules.
• Not a purifier. Penn State stresses that softening removes hardness minerals only. It does not make water safe from bacteria, nitrate or arsenic.

Maintenance

• Keep the brine tank stocked with salt and check for salt bridges.
• Check the hardness of softened water now and then with test strips to confirm the unit is regenerating.
• If iron passes through, resin may need cleaning or eventual replacement.
• Have an independent lab retest your raw water every few years, since well chemistry can change.

When to call a pro

Call a licensed plumber or water treatment professional if you need several treatment steps, if iron or sulfur is also present, or if local rules limit softener discharge. Your state health department or extension office can help interpret a lab report.