Best Water Softener Salt and Supplies
The best water softener salt for most systems is evaporated pellets such as Diamond Crystal Bright & Soft Pellets: the purest common type, so it leaves the least sludge in the brine tank. Below is what to buy for each job, from water softener salt to the test kit you should use before choosing a softener. Still choosing the softener? Start with our best water softener systems.
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How much water softener salt you'll use
A typical family of four on 10–15 gpg water uses roughly one 40 lb bag a month with a modern metered softener; very hard water or an older timer softener can double that. Water softener salt for hard water above 15 gpg goes faster still, so buy in bulk and store it dry. Keep the salt level a few inches above the water line in the brine tank, and break up any crust (a salt bridge) if the level doesn't drop for weeks. More upkeep tips in our water softener maintenance guide.
Best salt for water softener systems: what decides it
Purity decides it. Evaporated pellets are about 99.9% sodium chloride, solar salt is slightly less pure, and rock salt carries enough insoluble grit to leave sludge in the brine tank and clog the injector. The best salt for water softener use is therefore the purest one your softener's manual allows, in a form that suits its brine tank.
Best salt for water softener pellets or crystals?
Pellets suit almost every softener and are the safe default, especially in cabinet units with a small brine area. Solar crystals dissolve readily and cost a little less, but some cabinet makers warn they bridge more easily, so check your manual. Two-tank systems with a separate brine tank take either. Mixing forms is usually fine, but if you've had bridging, let one run down before switching. Potassium chloride pellets avoid adding sodium, at several times the price per bag.
Salt pellets: the default choice
Evaporated pellets are the purest common softener salt (around 99.9% sodium chloride), so they leave the least insoluble residue and are least likely to form a salt bridge or mush. If your manual doesn't say otherwise, buy pellets.
Diamond Crystal Bright & Soft Pellets
Evaporated salt pellets, the cleanest common softener salt, which helps prevent brine-tank mush.
- Weight
- 50 lb*
Morton Clean and Protect Pellets
Morton's everyday softener pellets in a two-bag pack.
- Weight
- 80 lb*
From our own use: We used Morton pellets in our iSpring install: three 40 lb bags filled the brine tank more than two-thirds.
Check priceUnder $60
Solar salt crystals
Solar salt is sea salt dried by evaporation in the sun. It dissolves slower and is slightly less pure than pellets, which suits some two-tank systems with large brine tanks but can leave more sludge in cabinet units.
Potassium chloride (sodium-free)
Potassium chloride replaces sodium with potassium. It costs several times more per bag and most makers recommend raising the salt setting, because it regenerates resin less efficiently. Worth it if you're on a sodium-restricted diet or want to discharge less sodium to a septic field. In our own GE Smart softener install, on our installer's advice, two bags of potassium pellets lasted more than six months.
Diamond Crystal Potassium Chloride
Sodium-free regenerant for people limiting sodium; costs more and you'll use more of it than salt.
- Weight
- 40 lb*
Resin cleaner
On well water with iron or manganese, a liquid resin cleaner added to the brine well every few months strips fouling that salt alone can't. Follow the maker's dose; several softener warranties name a cleaner schedule.
- Check priceUnder $60
Pro Products Res Care
Liquid resin cleaner that helps remove iron and fouling from softener resin.
Morton Universal Softener Cleanser
Resin and valve cleanser; Morton suggests a dose every few months.
- Use interval
- every 4 months*
Hardness test kits
Test before you buy a softener and after you install one. Strips give a band; a drop-count titration kit gives a precise gpg reading, which is what you enter into the softener's control.
- Check priceUnder $60
Hach 5-B Total Hardness Test Kit
Drop-count titration kit: count the drops to a colour change for a gpg reading, far more precise than strips.
Varify Hardness Test Strips
Quick dip strips that read hardness bands in gpg and ppm.
- Range
- 0-25 gpg / 0-425 ppm*
Sediment pre-filters
A spin-down screen or cartridge sediment filter before the softener stops sand and rust flakes from scoring the valve seals, which matters most on wells.
iSpring WSP-50 Spin-Down Filter
Reusable spin-down sediment screen for wells that send sand to the softener.
- Micron rating
- 50 micron*
- Pressure range
- 15-115 psi*
- Temperature
- 40-100 °F*
A. O. Smith Sediment Filter
Cartridge sediment pre-filter with a valve-in-head housing.
- Max flow rate
- 6 gpm*
- Rated capacity
- 24,000 gal*
- Warranty
- 1-year limited*
Replacement resin
Two-tank softeners can be rebedded with new cation resin when capacity drops after 10–15 years, for far less than a new system. Cabinet units are harder to rebed.
Purolite C100E Resin, 1 cu ft
Replacement cation softening resin for rebedding an older two-tank softener.
- Volume
- 1 cu ft*
Which supplies fit which softener?
| Softener type | Salt | Cleaner | Resin rebed |
|---|---|---|---|
| Two-tank (Fleck, Aquasure Harmony) | Pellets or solar crystals | Yes, in the brine well | Yes |
| Cabinet (Kenmore, EcoPure, GE, Aquasana) | Pellets preferred | Yes; follow the maker's schedule | Rarely practical |
| Salt-free (TAC) | None | No | Replace media per maker |
Searching for salt for a water conditioner? A salt-free conditioner uses none: it has no brine tank and nothing to top up. If a dealer calls your unit a "water conditioner" but it has a brine tank, it's a salt-based softener and takes the same pellets as any other.
Questions people ask
- What is the best water softener salt?
- Evaporated salt pellets for most softeners: they're the purest common type and leave the least sludge. Solar crystals also work in two-tank systems; potassium chloride if you want no added sodium.
- Can I use table salt or rock salt in a water softener?
- No. Table salt has additives and rock salt has insoluble minerals that build up as sludge. Use softener pellets or solar crystals.
- Can I mix pellets and crystals?
- It's usually fine, but mixing can encourage bridging. Let the tank run low before switching types.
- Is potassium chloride better than salt?
- It's sodium-free, which matters for some diets and septic systems, but it costs more and regenerates less efficiently, so you use more.