Best Water Softener Cleaners (and How to Clean Your Softener)
Quick answer: salt recharges the resin, but it doesn’t remove iron, manganese, silt and other buildup. A softener cleaner does. On well water with iron, use an iron cleaner like Pro Products Rust Out. For general upkeep, a liquid resin cleaner like Res Care, or your softener maker’s own cleanser, does the job. Whirlpool and Rheem both recommend theirs every four months, and using it can extend their warranties to five years. To clean the softener, pour the cleaner into the brinewell and run a manual regeneration. The calculator below works out how much to use.
Our picks:
- Best for iron: Pro Products Rust Out
- Best liquid resin cleaner: Pro Products Res Care
- Best for city water: OUT Filter Mate
- For Whirlpool softeners: Whirlpool WHE-WSC cleanser
- For Rheem softeners: Rheem water softener cleaner
- Easiest to find: Iron OUT powder
How we chose: we haven’t used these cleaners ourselves. We matched each one to the problem its maker says it solves, and took doses, ingredients and warnings from the makers’ product pages, labels and safety data sheets. Where a detail comes only from a seller’s listing, we say so.
Which cleaner for which problem
| Problem | Signs | What to use |
|---|---|---|
| Iron on the resin (well water) | Orange stains, iron in the softened water, hard water coming back sooner | An iron cleaner such as Rust Out or Iron OUT; Res Care also removes iron |
| General buildup (city water) | Slow loss of performance; silt, manganese or metal particles | A resin cleaner such as Res Care, OUT Filter Mate, or your softener maker’s cleanser |
| Bacteria or contamination | After service, after a boil-water advisory, or whenever you’re worried about contamination | Sanitize with household bleach as your manual directs (see below); a resin cleaner isn’t a sanitizer |
| Softener not drawing brine | Salt tank full of water, hard water | Clean the nozzle and venturi (see below), not the resin |
| Salt bridge or mushy salt | Salt level not dropping | Break up the crust; see how to tell if your softener is working |
From Pro Products’ and Whirlpool’s product pages and manuals.
If you have more iron than your softener is rated for, a cleaner only treats the symptom. See our iron guide to find out whether you need an iron filter first.
How much cleaner to use and how often
| Cleaner | First cleaning | Regular use |
|---|---|---|
| Rust Out (powder) | 1½ cups dissolved in ½ gallon of cold water | ½ cup per 40 lb of salt, layered in. Cabinet softeners: repeat the first cleaning periodically instead |
| Res Care (liquid) | 4 oz (½ cup) per cubic foot of resin | 4 oz per cubic foot of resin at each regeneration |
| Pro Softener Mate (powder, city water) | 1½ cups dissolved in ½ gallon of warm water | ½ cup per 40 lb of salt, layered in |
| Whirlpool or Rheem cleanser | The whole 16 oz bottle | Every 4 months |
From Pro Products’ product pages and Whirlpool’s and Rheem’s pages and manuals, checked October 2026. Older labels give smaller doses, so follow the label on your container.
Pro Products says most home softeners hold about 1 cubic foot of resin. Yours may differ: a 48,000-grain two-tank softener usually holds 1.5 cubic feet, and Whirlpool’s WHES48 holds 1.33. Check your manual, or see the sizes in our resin replacement guide. On iron water, Whirlpool also suggests setting the softener to regenerate every few days to keep the resin clean.
Water softener cleaner dose calculator
Pick your cleaner and enter your softener’s details to see how much to use.
Enter your softener’s details to see the dose.
How it works: doses come from Pro Products’ current directions for Rust Out and Res Care, and from Whirlpool’s and Rheem’s recommendations for their cleansers. Cups are rounded to the nearest quarter cup, and amounts under ¼ cup are shown in tablespoons. Always follow the label on your container if it differs.
How to clean a water softener, step by step
- Check your manual. Some softeners name a cleaner or warn against certain ones. Res Care isn’t for gel zeolite media, Pro Products says.
- Find the brinewell. Lift the salt lid and the brinewell cover. If your softener has no brinewell, wait until the salt is low and pour the cleaner straight into the salt tank, as Pro Products directs.
- Add the cleaner. Pour liquid cleaner straight in. Dissolve powders such as Rust Out in cold water first (see the table above).
- Run a manual regeneration. On Whirlpool softeners, press and hold the RECHARGE button for three seconds; Whirlpool says the recharge takes about two hours. The regeneration draws the cleaner through the resin and flushes the dissolved buildup down the drain.
- Rinse if needed. If you notice a taste, odor or discoloration afterward, Whirlpool says to recharge again, then run a cold tap just after the softener until the water tastes, smells and looks normal.
How to sanitize a water softener
Sanitizing kills bacteria; it’s a separate job from cleaning the resin. Whirlpool’s and Rheem’s manuals give the same method, which they recommend after installation or service:
- Pour about 3 oz (6 tablespoons) of household bleach into the brinewell.
- Make sure the bypass valve is in the service position.
- Start a manual recharge to draw the bleach through the softener.
- When it finishes, Rheem says to run about 50 gallons through a cold tap after the softener, which takes at least 20 minutes.
Rheem’s manual adds that on some water supplies, the softener may need sanitizing from time to time.
How to clean the nozzle and venturi
Whirlpool says this small part creates the suction that draws brine into the resin tank, and if sand, silt or dirt plugs it, the softener stops working. A salt tank full of water is the usual sign. Whirlpool’s steps, in short:
- Remove the top cover, put the bypass valve in bypass, and make sure the softener is in its service (soft water) cycle.
- Unscrew the cap on the nozzle and venturi housing, keeping the O-ring, and lift out the screen, disc, gasket and flow plug.
- Wash the parts in warm, soapy water and rinse them. A small brush helps with iron or dirt, but don’t scratch them.
- Reassemble in the same order, grease the O-ring with silicone grease and hand-tighten the cap.
- Return the bypass valve to service and run a recharge. The water level in the brinewell should drop.
How to clean the brine tank
Over time, sludge and salt residue can build up in the salt tank. The usual approach is to let the salt run low, put the softener in bypass, scoop out the remaining salt and water, wash the tank with mild soap and water, rinse it and refill. Our guide to the water softener brine tank covers normal water levels and what to do about too much water.
The best water softener cleaners
Pro Products Rust Out
A powder made for softeners on iron-bearing well water. Pro Products says it changes the rust and iron coating the resin into a clear solution that rinses away during regeneration, and that all softeners on iron-bearing water need it as preventive maintenance.
- Form: white powder with a sulfur smell; works by turning ferric iron into ferrous iron
- Dose: 1½ cups in ½ gallon of cold water for a first cleaning; ½ cup per 40 lb of salt for regular use
- Cabinet softeners: Pro Products says to use it for periodic cleaning only, repeating the first-cleaning dose
- Also cleans: rust stains on toilets, sinks, tubs and white laundry
Good to know: the 1.375 lb container on Amazon may carry an older label with a smaller dose; follow the label you have. Pro Products warns not to mix it with other chemicals, or use it with bleach or peroxide on laundry. More on iron in our iron guide.
Check price on AmazonPro Products Res Care
Pro Products calls Res Care the industry-standard resin cleaner, and it’s sold mainly through water treatment dealers. Pro Products says it removes iron, manganese, silt and metal particles from the resin bed, and it’s certified to NSF/ANSI/CAN 60 for drinking water additives.
- Form: liquid phosphoric acid mixture
- Dose: 4 oz (½ cup) per cubic foot of resin, poured into the brinewell; the same at each regeneration for maintenance
- Sizes: 1 quart, ½ gallon (RK64N) and 1 gallon; Pro Products also sells an automatic feeder
- Not for: gel zeolite media
Good to know: the Amazon listing is from a third-party seller, not Pro Products, so check that the bottle shows Pro Products’ Res Care label and part number RK64N. It’s a strong acid, so handle it with gloves and eye protection.
Check price on AmazonOUT Filter Mate
A gentler cleaner for softeners on city water. Its listing says it provides continual softener cleaning and removes light iron buildup (under 1 ppm) and low levels of calcium, lime, manganese, tannins, dirt and silt.
- Form: powder, 1 lb 6 oz; the listing names citric acid as the ingredient
- Best for: city water and light iron, not heavy iron
Good to know: these details come from the Amazon listing, which doesn’t give directions; follow the label. Pro Products makes a similar powder for city water, Pro Softener Mate, dosed at ½ cup per 40 lb of salt.
Check price on AmazonWhirlpool WHE-WSC Water Softener Cleanser
Whirlpool says its cleanser reduces the contaminants, iron and scale buildup that can clog the valve, and that it works in other brands too. The real reason to buy it if you own a Whirlpool: continuous use extends the 1-year parts and labor warranty to 5 years, or up to 10 on Whirlpool’s Pro Series models.
- Dose: the whole 16 oz bottle in the brinewell, then a manual recharge
- How often: every 4 months
- Formula: made by Pro Products; the safety data sheet lists 3–7% phosphoric acid
- Where to buy: Lowe’s
Good to know: check Whirlpool’s warranty terms for what counts as continuous use. On Amazon, listings titled “Whlpool Water Softener Cleaner” are sold under a generic brand, not by Whirlpool.
See it at WhirlpoolRheem Water Softener Cleaner
Rheem’s version does the same job: Rheem says it clears contaminants, iron and scale buildup from inside the softener, works with all brands and sizes, and needs no mixing. Regular use extends Rheem’s 1-year parts and labor warranty to 5 years.
- Size: 16 fl oz, ready to use
- How often: every 4 months
- Where to buy: sold only at The Home Depot
Good to know: Rheem’s page doesn’t give step-by-step directions or a safety data sheet, so follow the bottle and your manual. As with Whirlpool, Amazon listings titled “Rhem Water Softener Cleaner” are sold under a generic brand.
See it at RheemIron OUT Rust Stain Remover powder
Sold in many supermarkets and hardware stores, Iron OUT is mainly a rust stain remover, but its maker markets the powder for water softener iron removal too.
- Form: powder, 1 lb 12 oz bottles (the listing is a 2-pack)
- Best for: occasional iron cleaning when you can’t get Rust Out
Good to know: we couldn’t check Iron OUT’s current softener directions on its own site, so follow the water softener directions on the bottle and check your softener’s manual first.
Check price on AmazonWhat about Morton water softener cleanser?
Morton’s answer is in the salt rather than a separate bottle. Morton says its Clean and Protect pellets help keep resin tanks clean, and its Clean and Protect Plus Rust Defense pellets remove 10 times more iron than plain salt per regeneration, based on Morton’s own laboratory testing. Morton suggests keeping the salt tank at least half full and adding two bags every two months. If you own a Morton softener, check its manual for the cleaner it recommends.
Frequently asked questions
How often should you clean a water softener?
Whirlpool and Rheem recommend their cleansers every four months. On iron water, clean more often: Pro Products directs adding Rust Out with every 40 lb of salt, or Res Care at each regeneration. Pro Products also suggests sanitizing after the softener has been opened for service or after a boil-water advisory.
Can I use Iron Out in my water softener?
Yes, if your softener’s manual allows it: Iron OUT markets its powder for water softener iron removal. Follow the softener directions on the bottle. On a cabinet softener, Pro Products’ similar Rust Out is meant for periodic cleaning only, not layering in the salt.
Can I clean a water softener with vinegar?
None of the softener manuals we checked mention vinegar. They call for a softener cleaner for the resin and household bleach for sanitizing. Use a cleaner made for softeners, and don’t mix cleaners with each other or with bleach.
What is in Whirlpool water softener cleanser?
Its safety data sheet lists phosphoric acid, at 3–7%, as the hazardous ingredient, and names Pro Products, the maker of Res Care and Rust Out, as the manufacturer.
Is water softener cleaner safe for drinking water?
Cleaners made for softeners are designed to rinse out during regeneration, and Res Care is certified to NSF/ANSI/CAN 60 for drinking water additives. If you notice a taste or odor afterward, regenerate again and run a cold tap until it’s gone.
My softener is still hard after cleaning. What now?
Check the basics first: salt, the bypass valve, the clock and the hardness setting. Our “is my softener working?” checker walks through them. If those are fine, the resin may be worn out; see resin replacement or how long softeners last.
Related guides
- Best water softener for iron
- Water softener resin replacement
- Water in the brine tank: how much is normal
- How does a water softener work?
Sources
- Pro Products, Rust Out, Res Care, Pro Softener Mate and Sani-System product pages and directions, checked October 2026; Res Care sell sheet.
- Pro Products, Res Care safety data sheet (2010, hosted by Fresh Water Systems).
- Whirlpool, WHE-WSC Water Softener Cleanser and its safety data sheet (2015).
- Whirlpool, WHES48 installation and operation manual (2023): cleanser use, sanitizing and the nozzle and venturi.
- Rheem, Water Softener Cleaner and the RHS18 manual (sanitizing).
- Morton, Clean and Protect Plus Rust Defense and Clean and Protect pellets.
- Amazon listings for OUT Filter Mate and Iron OUT powder, checked October 2026.