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When and Why You Need a Water Softener and How They Work


The U.S. Environmental Protection Agency regulates the equality of tap water and does a fairly decent job doing so. There are nationwide regulations for more than 90 different water contaminants. However, as it doesn’t pose a threat to the public health, the federal agency does not deal with water hardness, which can become an expensive problem for you depending on where you live in the country.

On this page you will learn:

How to Tell if You Need a Water Softener

Let’s take a look at some statistics…

According to the U.S. Geological Survey (USGS) 85 to 90 percent of American homes receive hard water. So chances are high that the water coming into your house right now could do with some ‘softening’. By the way, the softest water can be found in Hawaii. The Great Lakes region in Alaska and Tennessee have moderately hard water. Texas, Kansas, California and Arizona have the hardest water levels.

There are obvious telltale signs that indicate that a water softener would make a good investment for your home, too, such as:

  • Stains on sinks and bathtub – Hard water is responsible for unsightly stains on your kitchen and bathroom sinks and armatures, and also in your bathtub. The stains are the result of evaporating water leaving behind lime that remains on the surface. A water softener removes calcium and magnesium carbonates, also called ‘hard water minerals’, which are the main component of lime. As a result, it becomes much easier for you to make both your kitchen and bathroom shine.
  • Stains on glasses and cutlery – You open the dishwasher to empty it and you wonder, did you accidentally forget to turn it on? Glasses and cutlery have white stains all over them. A clear sign for hard water.
  • Scratchy and faded towels – Clothes, bed linen and towels fade with time. But hard water accelerates the process and gives fabric that was once soft a scratchy and uncomfortable feeling.
  • Scale builds up in pipes and household appliances – Scale is a clear sign for hard water and it’s most dangerous as it clogs pipes and filters. As water flow rate in your house decreases, scale builds up even faster. Ultimately, pipes will wear out and might break in the long run. Your dishwasher starts leaking, because valves can’t properly function anymore. The overall lifespan of your household appliances drops dramatically.
  • Dry hair and skin – High amounts of calcium and magnesium salts in water can also cause your hair and skin to dry out. The consequences are itchiness and pesky dandruff. Even special shampoos and soaps can prevent this only to a certain degree.

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Test Your Water for Hardness

You might have observed some of the hard water signs in your home. But before you dive into the research process and try to find the best water softener deal, do yourself a favor and get a water hardness test kit first, as testing your water is the only way to know how hard it really is. A test kit can be purchased online for $20 USD an less.

Alternatively, you can request a water quality report from your municipal water supplier. In the report, look for grains per gallon (gpg) or mg/L of calcium and magnesium. If your water contains 7 gpg (about 120 mg/L) or more of both minerals added together it’s considered as hard water. The report is something almost all public suppliers have to provide for free. The only exception to the rule are companies operating private wells, which usually do not have to provide any information.

As a last option, you could also get your water tested by an independent lab, which isn’t the cheapest way of doing things.

Another way of testing your water for hardness:

Whether or not to buy a water softener is also a legal question. Salt-based water softeners are prohibited by law in some regions of the U.S. There are two main reasons behind the ban: The negative effect these water softeners have on the environment (they use a lot of water), and the additional expenses they bring along, as communities have to invest more resources into recycling softened water.

If you are considering to buy a water softener for your home, contact your local water supplier to find out if your state or municipality has placed any restrictions on what type of system you are allowed to use.

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How Do Salt-Based Water Softeners Work?

What do salt-based water softeners do? And what is inside of them? These are some of the most common questions we receive from our readers. It is understandable: People want to know how and if something really works, before they spend their hard-earned money buying it. Well, it’s time to shed some light into the dark…

What Do Water Softeners Do?

Simply put, water softeners remove minerals, first and foremost calcium and magnesium ions, from water that would otherwise cause what we refer to as “water hardness”. To be more precise, softeners not only remove these ions, they replace them with other ions, namely sodium and in rare cases potassium ions in a process called ‘ion exchange’.

What Is Inside a Water Softener?

If we examine the softening process in more detail, this is what we find:

  1. A water softener has two tanks. The first tank is called ‘resin tank’ or in rare cases ‘conditioner’. The second tank is called ‘brine tank’.
  2. The resin tank is filled with thousands of tiny resin beads, which are supercharged with sodium (or potassium) ions. All resin beads together are referred to as the ‘resin bed’.
  3. The resin tank is where our hard feed water flows into. The water passes through the resin bed and calcium and magnesium ions dissolved in the water replace the sodium ions that were attached to the reason beads. By the time the water reaches the bottom of the tank, it’s soft.
  4. Hard water ions are now attached to the resin beads. Over time and as more water flows through the tank, the resin beads become saturated. So, in order for a water softener to continue to work, the calcium and magnesium ions have to be washed off and the resin needs to be recharged with sodium. In other words, a water softener has to run through a ‘regen cycle’ to regenerate. This happens once, twice or more times per week depending on the respective water hardness and demand.
  5. Regeneration is where the brine tank comes into play. A brine tank is filled with sodium or potassium salt, usually in form of pellets or crystals. At the beginning of a regen cycle, water flows into the brine tank. It dissolves some of the salt and turns into concentrated brine. The brine is then injected into the resin tank to flush and recharge the resin with sodium. At the end of each regen cycle, the brine which now contains high amounts of calcium and magnesium ions is flushed down the drain and the softener can start working again.

Is Your Water Softener Causing Trouble? Stop Wasting Your Time and Let Our DIY Troubleshooting & Repair Guide Help You!

Water Softener Pros & Cons OR Why You Need a Water Softener

Benefits of Water Softeners

Household Appliances Last Longer + Lower Maintenance Costs

A water softener can extend the life span of water heaters, dishwashers, washing machines, coffeemakers, air humidifiers, and many more household appliances plus the entire plumbing system in your house by up to 30 percent. And in addition to that, your maintenance costs will drop significantly, as pipes and valves won’t clog up with limescale anymore.

Healthy Looking Hair and Skin

Soft water makes your skin and hair look and feel naturally healthy.

Easier Washing

There is nothing more frustrating than trying to work up a lather that refuses to form. You end up using a lot more soap than you otherwise would have if your water was not chock full of hard minerals. By removing these minerals, a water softener system will help you to do your cleaning faster, easier and more effectively. You also save more soap and detergent.

No More Stains

This is probably the most important benefit of all – especially for women! No more stains on glasses, cutlery, windows, etc.

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Disadvantages of Water Softeners

Water Wastage

In each regeneration cycle, a water softener uses up to 25 gallons of water and more to flush the resin tank. This adds up to more than 10,000 gallons in a single year, if you live in an area of exceptionally hard water, where a softener needs to go through a daily regen cycle.

Harder to Recycle

Softened water requires more resources to recycle in a water treatment plant than ‘normal’ water.

Not Suited for Drinking?

If you drink softened water or use it for cooking, your daily sodium/potassium intake will increase to a certain extent. Because sodium is found to be a factor in hypertension and high blood pressure, softened water might pose a health risk for genetically predisposed people under extreme circumstances. Another health factor is the lack of calcium and magnesium in the water. An easy workaround is to have a separate cold water line installed for your drinking water that does not get softened.

Additional Costs

Salt-based water softeners require electricity and salt for brine production. These are additional costs you have to cover.

Is Softened Water Safe and Healthy to Drink?

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Every couple of days one of our readers e-mails us, because he or she is concerned about the safety of drinking softened water. Somewhere online they read about the negative side effects water softeners might have on our health. We are, of course, talking about salt-based water softeners that add sodium or potassium to the water they process. And we want to emphasize that it’s a valid concern, especially for people that are on a low-sodium diet, because they are suffering from a coronary disease.

The WHO published a paper in 1996 called ‘Sodium in Drinking-water‘ and stated that domestic water softeners can raise sodium levels to over 300 mg/L, although much lower levels are usually found in softened water. Other research suggests that a conventional softener adds about 55 mg of sodium to each liter of average-hard water it processes. The sodium amount added to 1 liter of very hard water was measured at 118 mg.

So theoretically, even to people on a low sodium diet (1,500 to 2,400 mg per day), softened drinking water does not pose a real health threat, as the amount of sodium added to the water under normal circumstances is relatively small.

Nevertheless, We Recommend You to See Your Doctor Before You Start Using a Sodium Softener!

Other foods and drinks such as milk and orange juice might actually contain more sodium. For comparison purposes: A teaspoon of salt contains 2,400 mg sodium, a teaspoon of soy sauce 1,000 mg, a slice of white bread 170 mg, and 2 medium-sized eggs contain 110 mg sodium.

However, it is known that soft water is more corrosive with a higher affinity to leach heavy metals such as lead out of pipes and fixtures. As lead is a toxic substance, consider having your softened water tested to find out if it contains any of it.

Sodium vs. Potassium

If you don’t like the idea of added sodium in your water, you could also opt for a potassium ion exchanger (or buy a salt-free softener). Sodium vs. Potassium – is one better than the other?

Side Effects of Potassium Chloride

Potassium regulates the movement of water in and out of cells in the human body. It plays a major role in our metabolism, and it affects protein synthesis. The main source for potassium is our food. On a day to day basis, healthy adults should aim to intake about 4,700 mg of the mineral.

In our opinion, to regenerate a water softener sodium chloride makes a great choice, as it’s inexpensive and universally usable for all salt-based systems. However, if you are still concerned about the amount of sodium your softener could add to your water, you always have the option to fill your brine tank with potassium chloride instead. Potassium works the exact same way as sodium. Making the switch reduces your daily sodium intake and can benefit the environment, and your septic system and drainfield, too.

Health Concerns

Health concerns would be related to the consumption of drinking water treated by potassium-based water treatment, affecting only individuals in the high risk groups (individuals with kidney dysfunction or other diseases such as heart disease, coronary artery disease, hypertension, diabetes, adrenal insufficiency, preexisting hyperkalemia; people taking medications that interfere with normal potassium-dependent functions in the body; and older individuals or infants).‘ states the World Health Organization in a research paper. The WHO also advices high risk individuals to seek medical advice before installing a water softener in their home.

Added Costs

Both sodium and potassium chloride for water softeners can be found in home improvement stores. However, potassium is a little harder to find and more on the pricey end. A 40-pound bag costs about $10 USD. The average price for sodium chloride is $5 USD for the same amount of salt. Also, you would need to use more potassium to achieve a similar quality of regeneration as with sodium.

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If you have any questions or thoughts about water softeners in general, if you need one or how they work, please don’t hesitate to leave a comment below!

Leave a Comment:

Bob says a few months ago

Can I dump the resin tank over to pour the water out that’s in it ?
Will this make it lighter so that I can lift it out – get it out of the brine tank so that I can clean the bouth of them ? By tipping to spill the water out that’s in it will be causing any problems as far as the resin in the tank is concerned ?

    Gene says a few months ago

    Hi Bob,
    Although I can’t say this with 100% certainty, this shouldn’t be a problem. As long as the resin beads stay in place, everything should be fine. You are right, an empty resin tank is lighter than one filled with water.

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