Water softener brine tank (C) Daniel FriedmanWater Softener Cleaning & Sanitizing Procedures

  • SOFTENER CLEANING & SANITIZING - CONTENTS: How to clean & or sanitize a water softener or water conditioner. Cause, effects & cure for salt crusting or bridging, how to remove dirt & debris in the brine tank, how to disinfect or sanitize a water softener to get rid of bacteria, contamination, or rotten egg or sulphur odors, how to remove iron from the water softener, water treatment solutions, iron-out, water softener resins & cleaning compounds.
  • POST a QUESTION or READ FAQs about Cleaning & Sanitizing Water Softeners & About using a sanitizer in water softeners and the effect of sanitizers on septic systems

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Guide to Water Softener Cleaning & Sanitizing:

This article provides an owner's guide to water softener cleaning, and sanitizing - two steps in keeping a water conditioner working properly. We discuss the use of various chemicals & cleaners to sanitize or clean out water softeners and their brine tanks, and we comment on the effect of such chemicals on septic systems.

We discuss the formation of salt crust in the brine tank, the accumulation of dirt & debris in the brine tank, & how to remove these problems & contaminants in a water conditioner. We also discuss using iron removing products or other chemicals to clean & sanitize a water softener.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Owner's Guide to Cleaning & Sanitizing the Water Softener / Water Conditioner Brine Tank

Photo of a water softener salt tank ready for cleaning

[Click to enlarge any image]

Article Contents

If your water softener does not seem to be working or is not working properly, also see DIAGNOSE WATER SOFTENER PROBLEMS

Also see SOFTENER ADJUSTMENT & CONTROLS for details of water conditioner controls, how they work, how to set them.

Separately at INSTALLATION of WATER SOFTENERS we discuss how this equipment should be installed.

If your water softener is not working, see DIAGNOSE WATER SOFTENER PROBLEMS.

Our photo at left shows the interior of a water softener salt tank. Notice that brown soil line marking where dirty water has risen in this tank? Our photo at right shows a close up of the inside of the float tube in the water softener tank - it's the same yellow tube you see in the left hand photo.

Although the salt you dump into the water softener's salt reservoir tank looks clean, the salt you have purchased is usually mined from the earth and will contain small amounts of soil and other debris. The debris accumulates in the water softener salt tank over time and can become filthy and possibly unsanitary. Debris in the salt tank can also clog water softener controls.

We recommend waiting until the salt in the tank has been consumed, or nearly all consumed. This will leave a water softener salt reservoir tank which is nearly empty and which is quite light, making it easy to disconnect, carry outside, and hose out.

Be careful not to break the float controls in the softener tank, but if you do break something or if you find that the float no longer moves freely, this part can and should be replaced.

Check the water conditioner brine tank for salt crusting or salt bridging

If a water softner is not softening the water and appears to have power and runs through regeneration cycles, taking a look into the salt or brine tank can fool you. The tank can look "full" of salt crystals or pellets but if the top of the salt has crusted or formed a hard bridge stuck to the sides of the brine tank, in fact no salt may be dropping into the tank water to form a brine solution.

First though, to avoid some embarrassment, check that the water softener is not in "bypass" position. Now take a look in the salt tank.

A salt crust may form on the sides or across the whole interior surface of the brine tank. Periodically you should break up and remove this scale as it may prevent proper water softener operation. For example a thick salt crust may prevent salt in the tank from falling freely to the tank bottom where it is needed to mix with water during the regeneration cycle.

To avoid salt bridging or crust formation or to break up the salt bridge Sears advises:

Sometimes, a hard crust or salt “bridge” forms in the brine tank. It is usually caused by high humidity or the wrong kind of salt. When the salt “bridges,” an empty space forms between the water and the salt. Then, salt will not dissolve in the water to make brine. Without brine, the resin bed is not recharged and hard water will result. If the storage tank is full of salt, it is difficult to tell if you have a salt bridge.

A bridge may be underneath loose salt. Take a broom handle, or like tool, and hold it next to the water softener. Measure the distance from the floor to the rim of the water softener. Then, gently push the broom handle straight down into the salt. If a hard object is felt before the pencil mark is even with the top, it is most likely a salt bridge.

Gently push into the bridge in several places to break it. Do not use any sharp or pointed objects as you may puncture the brine tank. Do not try to break the salt bridge by pounding on the outside of the salt tank. You may damage the tank. - "Kenmore Model / Modelo No. 625.384200 Water Softener with Ultra Flow Valve retrieved 4/20/14, original source: [copy on file]

Check the water softener brine tank for dirt and debris build up

Water conditioner salt sample (C) Daniel FriedmanWhen salt is low in the tank check for an accumulation of dirt and debris.

Salt is a naturally-mined mineral that is dug out of the ground. Although it looks (and is) pretty clean when you dump salt into your brine tank, a bit of soil (earth, dirt) comes along with it and may accumulate in the bottom of the brine tank.

So even though the salt looks clean and beautiful (our photo at left) when you are pouring it into the brine tank, in fact it may contain soil particles or other debris.

Because soil particles (dirt) does not dissolve and pass out of the system during the backwash/regeneration cycle, it accumulates in the bottom of the water softener brine tank where eventually it looks like muddy water.

You won't see this dirty crud because it's always hidden by the new salt you keep pouring on top of what's already in the brine tank - until you allow the water softener to "use up" its salt enough that you're looking at a nearly-empty brine tank.

When your water conditioner's brine tank looks dirty just empty it out and wash its interior with an ordinary household cleaner or detergent.

See Basic Procedure To Clean or Sanitize a Water Softener and Detailed Procedure to Clean & Sanitize a Water Softener.

Watch out: Some water softner companies such as Sears advise against using rock salt, recommending pellet salt or similar products because some rock salt contains soil and other debris that can clog the water softener.

Use NUGGET or PELLET water softener salt. DO NOT use rock salts, as they have dirt and sediments that will stop the softener from working. To maintain optimum performance of your water softener, the salt tank should be cleaned out every 2 to 3 years- "Kenmore Model / Modelo No. 625.384200 Water Softener with Ultra Flow Valve retrieved 4/20/14, original source: [copy on file]

Sanitize New Water Softener Installations

Reader Question: do I need to disinfect or sanitize a new water softener at time of installation?

(Apr 19, 2014) C.S. said:

Do you need to sanitize a new soft water machine? After ours was installed by a technician and ready to go, I read installation manual that said to sanitize with bleach before using.


C.S. I haven't seen that specification but certainly if the manufacturer recommends such a step (some do) I'd follow their recommendations.

Can you tell us the brand and model? I'd like to take a look at the instructions as well. Daniel

Reader follow-up:

Thanks for answering. It's a Kenmore 420 Series. It's just annoying that the installer sent by Sears got it all set up, programmed it, told us we could add the salt, but didn't mention anything about the sanitizing. - C.S.

Reply: Sears Kenmore water softener manual recommends sanitizing new equipment installations

Indeed on p. 14 of the Sears Kenmore 420 water softener installation manual the company recommends disinfecting the equipment when it is newly installed, using 3oz of household bleach in the brinewell and running a regeneration cycle followed by 50 gallons of flush-out to remove bleach from the system before placing it in service. It's good advice considering that plumbing fittings, equipment and devices are not kept in absolutely sanitary conditions prior to installation. It's also cautious advice.

There are probably millions of water softeners installed that were never intitially sanitized though they may beg for that treatment after having been in service for a time, particularly if contaminated by water that itself contains bacteria or by rock-salt that contains soil and debris.

If you like you might wait until your unit has consumed the salt in the brine tank, then go through the sanitizing advice the company recommends, rather than trying to shovel out the salt already therein.

If you have any doubt about the potability of your water supply, be sure to test that as well, taking a sample from a point ahead of all of your water treatment equipment.

Water Softener Sanitizing References

How to Sanitize a Water Softener or Water Conditioner

All salt used in water softeners, whe3ther it is "rock salt", "salt pellets", "solar salt" or "evaporated salt" is a natural mineral that will contain impurities and possibly soil particles. These materials accumulate in the bottom of the salt tank during normal use and eventually can interfere with water softener operation or water quality.

Every year or two we let the water softener use up its salt so that we can inspect and remove any dirt or sludge that may have accumulated at the bottom of the salt tank. The following procedures are given in both basic and detailed forms and are adapted from maintenance recommendations from Culligan™ and other water conditioner companies.

If your water softener has been shut down for a week or more, if you are restoring to service a building that has been winterized (WINTERIZE WATER SOFTENER), or if your building water supply both hot and cold water have a stinky sulphur smell or "rotten egg" smell (caused by harmless but nasty smelling sulfate-reducing bacteria), you'll want to try the sanitizing procedure we describe below.

If only the hot water supply in the building smells like rotten eggs, see ANODES & DIP TUBES on WATER HEATERS..

Also see How to Identify Odors in Drinking Water.

Basic Procedure To Clean or Sanitize a Water Softener (and its salt reservoir or brine tank):

  1. Turn off any other water treatment equipment that uses Sodium hydrosulfite, Sodium bisulfite, or any other reducing agent and disconnect that device temporarily. If you're not sure what your other water treatment equipment is, ask your plumber or water treatment company who installed it.

    If you are not the original owner of the building and don't know who installed your equipment, look on the equipment for its name, model number, and for a sticker that may identify the local installer.
  2. Run a manual regeneration cycle to flush out the equipment;
  3. Put 3 gallons of water into the salt tank. Generallyour instructions prefer that you have removed all salt from the brine tank and have cleaned it of any visible mud, crud, or debris, and that you've checked that the brine tank float tube is also clean and that the float moves freely.

    This is the most thorough cleaning approach. However some water softener manuals (such as the Sears Kenmore 100 / 150 UltraSoft) note that you can perform this sanitizing cyle with or without salt in the brine tank.
  4. Add bleach to the brine tank:

    For the Sears Kenmore 100-150 series water softener (others are similar) the company suggests adding 3/4 ounce or 1-2 tablespoons of 5.25% unscented household bleach to the water in the brine tank. Examples of "Household bleach" brands include BoPeep bleach, Clorox bleach, Eagle bleach, Linco bleach and White Sail bleach.

    Other directions use much more bleach, suggesting that you pour a one cup of household bleach (if your water softener is a 9" diameter unit) or two cups of bleach (if your water softener is a 12-inch diameter unit) right into the salt tank.

    We pour the bleach into the yellow tube that houses the float assembly but don't do this and let the bleach sit there for days since it might be so concentrated as to damage water softener parts. Just go ahead to the next step.

    Watch out: using more bleach is a more aggressive sanitizing process that may require extra regen cycles to flush all of the bleach out of the system.
  5. Run an extra manual water softener recharge cycle: set the water softener to perform an extra (manual) recharge cycle.

    The control to run an extra regen cycle varies by water softener brand or model. On the Sears Kenmore 100 / 150 series water softeners that use an electronic control head you'll have to press and hold the ON/OFF-HOLD button for three or more seconds to start a recharge / regen cycle. The regeneration cycle may take about two hours.

    This will flush salty chlorine disinfectant through the equipment. (No, using the recommended quantity of bleach will not harm the septic system.)
  6. Add salt? If you performed sanitizing of the water softener with no salt (or potassium chloride KCl) in the brine tank remember to now re-fill the salt tank with your salt supply.

Detailed Procedure to Clean & Sanitize a Water Softener Salt Salt Storage Tank

These instructions presume that your water conditioner (water softener) uses a separate salt or brine tank. The following instructions are adapted from advice from Culligan.

You will need these tools to clean out the salt storage tank

Water softener brine tank (C) Daniel Friedman

Remove the cap from the brine valve chamber. The brine valve chamber is the smaller diameter vertical tube that you will find inside the salt tank when you have removed the tank's cover.

Our photo (above-left) shows the interior of a salt tank or "brine tank" with the cover removed. The yellow tube is the brine valve chamber. Brine valves are discussed and illustrated at SALT DOSE SETTING, WATER SOFTENER.

[Click to enlarge any image or table]

Photo of a water softener salt tank ready for cleaning

Now we are ready to put the water conditioner salt tank and its controls back together.

How to Clean Iron (or other) Sediment out of a Water Softener

Some water softener salt products already include an additive to improve the ability of the water softener to remove iron from the building water supply.

Watch out: if you are using a salt that includes an iron-removing additive, you'll need to use a water softener resin bed cleaner periodically as well. For Sears Kenmore water softeners the company sells a resin bed cleaner:

Sears Resin Bed Cleaner # 42-34426 available from the company.

Question: Using Iron Out™ (sodium hydrosulfite) to remove iron deposits from the water softener resin tank: reduced water pressure traced to water conditioner resin tank fouling

Iron stains on bathroom sink (C) D FriedmanMy existing Culligan water softener is 22 years and has in place between it and the water supply an iron filter, which does a good job in removing iron.

[Our photo at left illustrates iron staining on a bathroom sink - Ed.]

But like all filters of any sort do not filter 100% of a substance. Unnoticed over the years, until at some arbitrary point is reached, the flow rate over the years at the tap was reduced. This was found to be iron fowling in the resin in our water softener tank.

But prior to that fact Culligan personnel were telling me that the water conditioner unit should be replaced. I did further research into this problem.

Initially I did not suspect it was iron fouling because I had an iron filter installed ahead of the water conditioner.

The solution to this problem turned out to be simple. From the hardware store I obtained a powder to remove iron from any thing. I followed the instructions on the container for a softener. By repeating the instructions three times, once at each recharging cycle, the problem was solved over about nine days.

The product for removing iron is called 'Iron Out' The principle ingredient is sodium hydrosulfite, which is used in some application as a water conditioner. - M.P.

M.P. continues:

I was not too concerned about residue of the product in the softened water as all water that is used for human and pet consumption is drawn before the softener but after the iron filter, therefore, I cannot answer the question about possible poisoning or resin damage.

Independent of the iron removing product, we prefer not to drink conditioned water because of the sodium content and the lack of calcium and magnesium, of which those two ingredients are in my opinion beneficial to health. My softener is a Culligan Mark 88.

The softener consists of a brine tank and a resin column with the controls on top of the column, probably a unit that's quite standard to others. - M.P.

Watch out: There could be health hazards from drinking or bathing in water produced by a water conditioner or other water treatment equipment after running cleaning chemicals through the system.

Any chemicals used to try cleaning or sanitizing a resin tank should be thoroughly flushed out of the system. It should be easy to do this by repeating enough water softener backwash or "regeneration" cycles. See the Super Iron Out usage instructions from the manufacturer, below, and see the MSDS for that cleaner also found just below.

Watch out: And could the iron remover damage the water conditioner resin? Check with your water softener manufacturer before trying this.

Iron and Rust removing Chemicals & Stain Removers are available from a number of manufacturers including

Water Treatment Solutions using Iron Removing Chemicals (Super Iron Out)

According to Summit Brands in discussing the use of Super Iron Out to clean a water softener system:

Does your water softener make your water taste bad? Water softeners and heater tanks need regular maintenance to operate efficiently and effectively. Rust never sleeps. Using Super Iron Out on a regular basis knocks rust out before it stains your home's surfaces.

Water Softener - First Application — Use 1 cup (250 mL) Regular Use - Use 1/4 cup (62 mL) All softeners treating high iron content water require Super Iron Out as preventative maintenance and to eliminate iron buildup.

First Application of Iron Remover in a Water Softener

  1. Add 1 cup in 1/2 gallon of cold water
  2. Pour directly into brine well (for softeners with no brine well, pour directly into salt tank when salt level is low)
  3. Manually regenerate softener
  4. Repeat for heavily fouled unit.

Regular Use of Iron Out in Water Softeners

  1. Add 1/4 cup per 40 lbs. of salt
  2. Repeat regularly for continuous treatment

Note: If taste or odor is detected in tap water, manually regenerate softener again, then run cold water until odor is gone. For cabinet models, use for periodic cleaning only. Follow First Application instructions above.

Please follow cautions and instructions on the label carefully.

MSDS Material Data Safety Sheet for Super Iron Out rust and stain remover.
- Reference: web search 01/31/2011, adapted from original source:

MSDS Material Data Safety Sheet for Pro Rust Out, rust and stain remover, Pro Products, contains sodium hydrosulfite & sodium bisulfite. Warnings include against inhalation, eye and skin contact, ingestion (which would include drinking). Overexposure can exacerbate asthma or lung disease. [3]

See RED STAINS from WATER SUPPLY for more about removing iron from the building water supply system.

Water Softener Cleaning Using Manufacturer-Recommended Resins or Cleaning Compounds

Sears Kenmore water softner cleaning resin - about $20. from SearsUsing a water softener cleaner or resin cleaner can improve water softener operation and keep parts working longer according to both manufacturers and independent experts. [19][20]

Sears Kenmore water softener instructions for some models point out that consumers can buy water softner salt that includes an iron removing additive, increasing the water softener's ability to remove iron content in the water supply along with minerals associated with hard water.

That manufacturer recommends using a special water softener cleaning resin provided by the manufacturer.

Some salts have an additive to help the softener handle iron in the water supply.

These salts may be used if your water supply has a high iron con tent. It is recommended to use Sears Water Softener Clean er (refer to the parts list in back of manual for part number) for periodic treatments to keep your resin bed clean.

Where to Buy Water Softener Cleaners & Sanitizers

The following products are sold and described as specifically designed for use in water softeners and water conditioners:

Take a look at Michele Hébert's Water Softeners Annual Maintenance [separate PDF from the University of Fairbanks Cooperative Extension] for more detail about chemicals & processes used to clean water softeners.

Question: how do I clean the water softener?

(Aug 31, 2014) Antoinette Jackson said:

We are NEW to this water softening sytem of life here in Palm Bay, Florida. Been trying to learn, learn, and learn some more.

We do not have hundreds of dollars to pay these companies to come out and do what we could do ourselves. Example we looked inside of the water bubbler holding tank (it is located outside) and were absolutely appalled at the filth, algae, rust, grime etc in the tank it had obviously not been cleaned in the 7 yrs this house has been here. So PLEASE someone tell me where to start to try to clean this MESS out! I grosses me out I have been brushing my teeth with this water! I don't think the reverse osmosis filter I have under my kitchen sink can even help this mess!

Does ANYONE KNOW of a reliable/responsible person we can pay to come clean the tank out? We are 60 now and I am not in good health. My only idea is a mop and gallons of bleach, but there are PVC pipes going across the inside near the top and two others coming INTO the tub on the left also. I need help! Has anyone out there cleaned there own and can tell me how you did it? I'd really appreciate any help and tips. Thank you Antoinette Jackson islandantoinette AT yahoo is my e mail too. If you'd like to write me directly.

(Aug 31, 2014) Antoinette Jackson said:
OH sorry if it matters I have the manual I found which says it is a GE then it says it is an Autotrol® Brand 255 Valve / 400 Series Controls. I looked it up and sure enough there is the same manual. Not that I can understand any of it. But this page certainly looks like I can start here to begin to figure it all out IF SOMEONE CAN TELL ME HOW TO CLEAN THE HUGE OUTSIDE BUBBLER TANK THAT SEEMS TO HOLD THE WATER.

There is a VERY BIG valve on the bottom I can drain it. But to get those pipes out to tip it over to clean it, I'd have to use a hack saw and cut them then make sure I had more to re do it, with the PVC glue and if I do something wrong YIKEES! Has anyone cleaned theirs?????? Please give any advice Thank you! Antoinette Jackson If I even could find someone to clean this big Plastic Holding Tank what would it cost me? And other than just bleach and a mop and LOTS and LOTS of HEAVY HEAVY scrubbing on ones hands and knees IF we can get it turned over to do it, any other way to do this????
It says on the side in big Red Letters R&S



Most water treatment companies will be happy to send a trained service technician to inspect, clean, and also instruct you in the use of your water conditioner. They hope to sell you salt, service, etc.

In the More Reading links just above, see


for those instructions.

Cleaning & Sanitizing Water Softeners & Using a sanitizer in water softeners - the effects of sanitizers on septic systems

Question: Will using BioSafe™ sanitizer in the water softener harm the septic system?

We have been doing business with a company called Biosafe and have not be satisfied with the results. I am referencing your article on line “Water Softeners – water softener effect on drinking water and on septic systems" [found at SALT OR WATER INTO SEPTIC].

As I understand the fine print on page 1, you are saying you do not recommend this product. My husband read it just the opposite….that biosafe is one of the recommended products. Could you please clarify. - B.R.

Reply: BioSafe's Hydrogen Peroxide and Peroxyacetic acid - based sanitizers

BioSafe's Hydrogen Peroxide and Peroxyacetic acid - based sanitizers, used as directed, should have significantly less impact on the environment (and therefore on a residential septic system) than certain other chemicals used as sanitizers or disinfectants. But be sure you were using the right product for the right application and in the proper manner.

The article you cited, found at SALT OR WATER INTO SEPTIC - does not discuss Biosafe nor any other specific sanitizer or disinfectant, but perhaps you saw a Google-placed a Biosafe ad at the top of our page.

The "fine print" to which you refer may have been our statement affirming our independence from any advertisers, products, or services that I quote here:

Our site offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. Our contact info is at

I took a look at a Biosafe site ( that may be the source of the product you asked about: BioSafe Systems LLC - but you should confirm that this is the company whose product you are asking about.

BioSafe Systems produces a wide range of sanitizing products used in agriculture, animal health, greenhouses, water and wastewater industries, food safety, turf, pond and lawn care, and general sanitation.

The BioSafe product line, as I read the company's information on general sanitation, is based on activated peroxygen sanitizers marketed as an alternative to chlorine, phenol, and quat-based formulas. Even as a layman not a chemist, it is easy to understand the basis of the company's assertion that their approach is less harsh and less persistent in the environment than some of the alternatives.

Here you can see a list of links to MSDS sheets for BioSafe™ products:

Of their products, and not knowing which Biosafe product you're interested in, I looked at SaniDate 5.0 Sanitizer/Disinfectant a sanitizer described at

The BioSafe MSDS shows that the hazardous components of this product are Hydrogen Peroxide and Peroxyacetic acid - two very common and widely used disinfectants that are less dangerous to the environment than some other chemicals because the products are not cumulative in the environment.

BioSafe says that the product degrades 99% in 20 minutes. That's quite a good argument supporting the assertion of no bioaccumulation. It's worth noting that the product is however in direct contact acutely toxic to fish, crustaceans, and bacteria (bacteria was probably its target in the first place, no?)

Watch out: at BioSafe's website I did not read specific advice addressing use of their products in a residential water softener. I have asked the company for more information and advice.

In Sum:

I am not an expert in the field, but as a general researcher/investigator I interpret the information about the product to indicate that the product, used as directed by its producer, and at normal levels and frequency of household use, is unlikely to damage a septic system drainfield.

Your husband is right in intent (product OK) but wrong in a literal sense (we do not recommend specific products) - the product does not look harmful to the septic system, with how-to guidance from the manufacturer might be fine for sanitizing a water softener, but in particular, we do not recommend specific products or services. (Google ads support our website; to avoid any conflict of interest, we have no relationship whatsoever with products or services advertised or discussed)

Further details needed:

Please tell me what product you were using, why you are not satisfied with the results, and keep me posted on how things progress in your own case, let me know how you were intending to use the product, and send along photos of any equipment (like water softener) involved if you can.

Such added details can help us understand what's happening and often permit some useful further comment.

Also if you were dissatisfied with a BioSafe product you should contact the company to assure that you were using their product for an application that they recommend, and in the manner that they recommend for that use.

What we both learn may help me help someone else.

Question: Is it Ok to Use Pro Rust Out as regular water softener maintenance, sodium hydrosulfite and sodium metabisulfite, in a water softener

I have added Pro Rust Out very occasionally in small measures to our water softener as a maintenance measure. Pro Rust Out contains sodium hydrosulfite and sodium metabisulfite. Will these chemicals make our water unsafe for drinking? Thank you so much for your reply. Jon

Reply: Used as directed these water softener cleaning products should be safe. Here are details, examples of use, usage instructions, & health warnings.

The product you ask about, Pro Rust Out™, is produced and sold by Pro Products [3], a company that distributes a line of water softener cleaning products. Quoting, the company produces:

Water softener cleaners designed to clean, restore and maintain the life of water softeners. These products are formulated to treat water softeners with iron issues or for daily preventative maintenance.

Rust Out softener rust remover chemically removes iron and rust build-up that coats the resin beds and fouls the softener. This iron build-up is not totally removed during normal regeneration of a water softener.

Using Rust Out softener rust remover in a water softener will eliminate rust and foreign matter from the resin bed. This increases the life of the softener and reduces rust staining on household fixtures and other surfaces. Use the softener rust remover regularly as preventative maintenance to ensure the softening and recharging efficiency of the softener's resin bed.

Usage Instructions for Pro Rust Out™ water softener cleaner:

Water Softeners: Rust Out softener rust remover dissolves the iron in the mineral bed and is rinsed from the softener much the same as salt brine.

First Application: Dissolve 1 in 1/2 gallon cold water. Pour directly into brine well (softeners with no brine well, pour directly into salt tank when salt level is low). Manually regenerate softener. Repeat for heavily fouled unit.

Preventative Maintenance: Add 1/4 cup for every 40lbs. of salt added to brine tank. Layer to ensure a continuous dose with each regeneration.

General Purpose Cleaning: Our softener rust remover works on dishwashers, dishes, glassware, white clothes or fabrics, and water softeners - follow directions on the back of the package.

Information about the use of sodium metabisulfite and sodium hydrosulfite in water treatment equipment:

Sodium metabisulfite (Na2S2O5) is an inorganic compound used as a disinfectant, antioxidant, or preservative. Its uses include both as a food additive and as a sanitization and cleaning agent. It is also used in some medical applications such as in the EpiPen. [4] Sodium hydrosulfite (Na2S205) is used as a cleaning agent for reverse osmosis water treatment equipment. [2]

In sum, the company's instructions indicate that used as directed (1/4 cup for every 40 lbs. of salt added) for regular water softener maintenance, the product should be safe. Certainly it would appear that the concentration of sodium hydrosulfite and metabisulfite will be very low in the building water supply.

Concentration of sodium metabisulfite and sodium hydrosulfite in water processed through a treated water softener

If we use a guesstimate of 4 pounds of salt used per water softener regen cycle (check your machine's actual salt dosage level) that would place an average of about 0.025 cups (1/4 divided by 10) of chemicals in the water used to clean and regenerate the water softener during a regen cycle.

Furthermore, as that water is supposed to be flushed through and then out of the water softener resin tank during the regen cycle, only a low level of salt + Sodium Hydrosulfite and Metabisulfite would be expected to remain inside that resin tank and to come into contact with drinking water during subsequent use.

Watch out: that analysis presumes that a water softener is adjusted and working properly and that you are using the cleaning agents as recommended by the manufacturer. To do otherwise could be unsafe. For example, used in concentrated form, sodium metabisulfite is even used to remove tree stumps! [4]

At SOFTENER CLEANING & SANITIZING (above) we have provided further comments on the use of sodium hydrosulfite on water softeners and on the safety of drinking or bathing in such treated water.

The bottom line advice on water softener treatment using sodium hydrosulfite and metabisulfite

The bottom line is that while such chemicals may be effective in cleaning out iron and sediments, it is very important to thoroughly flush the system before returning the water softener to operation, or there could be health hazards from chemicals that enter the water supply from chemicals left in the resin tank.

That article includes recommendations for safe levels of usage of several water softener cleaners and treatments. We also include links to health and safety information (MSDS forms) and information for the chemicals involved. I've checked and added information about the second chemical you name, sodium metabisulfite.

In general, should a more harsh treatment or cleaning be needed at a water softener, it may be acceptable do to so provided the system is adequately flushed and cleaned afterwards.

It's possible to thoroughly flush and clean out a resin tank if it has first been emptied of all salt (and any dirt and debris are of course first manually cleaned.

On the other hand, it would be quite difficult to thoroughly flush cleaning or treatment chemicals out of a water softener and brine tank if the tank remains full or partially full of salt. So many repeated flush cycles would be needed that you'd be wasting both water and salt.

And if the building is served by a private septic system there could be a risk of flooding or damaging the drainfield by that added water and salt volume as they would exceed normal usage levels.

Also you'll note that we warned that some water softener resins might be damaged by some cleaning chemicals. Check with the manufacturer of your water softener or its resin content.

Question: Do I Need to Add Water to the Salt Tank After Cleaning it Out?

I had to take all of salt out because it was getting to hard and water was above the salt. When I put new salt in should I also add some water? - Brian

Reply: No, water will be placed into the salt tank by the softener control during the next regen cycle

Brian you do not need to add water to the water softener brine tank when you have emptied, cleaned, and then refilled the tank with salt. The water softener regen cycle and float control will automagically put the correct amount of water back into the salt tank.

Reader Comment:

If all the water is emptied out of brine tank upon cleaning, depending on model of softener, you might need to add water. All the fleck valves need water added. Kinetico and possibly culligan do not.

A. Carlin Water tech. - Jan 2012


Thanks so much Carlin Water Tech. Contact us if you want to be listed and linked-to as an expert resource.

Question: is water softener resin dangerous

Resin broke through to our pipes and came out our faucets. Is this dangerous to our health in any way?



Naturally it's not good to drink particles or debris of any sort. Presuming you are talking only about a conventional water softener that uses a resin tank and salt (that is not a treatment system that includes more dangerous chemicals) the drinking water that you were consuming before was passing through that very resin.

However the resin risks clogging pipes and valves and faucets and needs to be flushed out.


(Nov 12, 2012) Using Starsan to sanitize my GE said:

I am wondering if it would be alright to use Starsan to sanitize my water softener. Starsan from, is a phosphoric acid based product. It is promoted as a 'no-rinse' sanitizer and is often used in food preparation environments, most notably in breweries.

I would like to use it instead of bleach, but am concerned with two things. 1- any negative affect to the water softener or drinking water. 2- it has a foaming nature, will this cause damage?

Reader question: is it ok to use Potassium Chloride instead of regular salt in my water softener?

My water softener installer says we should use potassium chloride rather than salt in our water softener. Is that a good idea?

Reply: Sears has the following advice that you should follow if using potassium chloride (KCL) instead of sodium chloride or "regular salt" (NaCL) in your water softener:

POTASSIUM CHLORIDE (KCl) SALT If you choose Potassium Chloride (KCl) as a regenerant, following these suggestions will help give you years of maintenance free service.

1. Place only one bag of KCl in your softener at a time (the salt storage tank should contain no more than 60 pounds of KCl at any one time).

2. A softener using KCl should not be placed in areas with temperature fluctuations and high humidity (KCl will harden in these environments and may make the softener inoperable).

3. Check the brine tank and brine well (black tube in salt storage tank) monthly. If hardening is present, pour small amounts of warm water onto hardened areas until they loosen.

4. Be sure to set “Salt Type” on the controller to “KCl”. This setting adjusts the regeneration cycle times to compensate for the different rate at which KCl dissolves. See “Set Salt Type” on the previous page. - "Kenmore Model / Modelo No. 625.384200 Water Softener with Ultra Flow Valve retrieved 4/20/14, orginal source: [copy on file]

Persons who are on sodium restricted diets should consider the added sodium as part of their overall sodium intake. For example, if your water supply is 15 grains hard, and you drank 3 quarts of softened water you would consume 335 milligrams of sodium. That is equivalent to eating 2-1/2 slices of white bread  - "Kenmore Model / Modelo No. 625.384200 Water Softener with Ultra Flow Valve retrieved 4/20/14, orginal source: [copy on file]


Continue reading at OTHER WATER SOFTENING METHODS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

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