Which Water Softener Salt Is Best for Your System?

Hard water can be a major annoyance for homeowners. Though not a health hazard, this mineral-filled water will eventually clog up pipes, cause damage to appliances, and result in stained sinks and bathtubs, among other frustrations. Luckily, science has blessed us with the hard water softener. This modern marvel uses positively charged ions to eliminate all of those heavy minerals from your water supply, resulting in pure H20 that is as soft as morning dew. 

Once you hire a professional to install a water softener, you’ll have to regularly maintain the system. This means keeping the brine tank stocked with water softener salt, as this salt is a key player in the chemical reaction that turns hard water into soft water. But what types of water softener salt are available, and which is best for your system? It’s actually pretty simple.

Types of Water Softener Salt

There are several different options when it comes to which salt to place in your softener’s brine tank, but most systems can handle anything you throw at it. There are, however, some benefits and disadvantages to each choice that are worth considering.

Sodium-Based Water Softener Salt

Of course, most products available for purchase are manufactured using sodium, or more specifically, sodium chloride. Sodium chloride is easy to find, inexpensive, and highly efficient. The downside? Well, it’s sodium. Those on salt-restricted diets may not want to add more to their water supply, even if it only totals around 30 milligrams of sodium for each eight-ounce glass of water.

Sodium-based water softener products are available as pellets, crystals, and block salt. Pellets and crystals are virtually interchangeable but talk to your favorite plumber before adding block salt. These large blocks may not dissolve in the brine; they only work in special tanks.

Pros

• Highly effective at softening water

• Compatible with most water softening systems

• Relatively easy to use

Cons

• Might not work for people on low-sodium diets

• Not suitable for all plants

• Can increase sodium concentration in wastewater

Rock Salt

Rock salt is by far your cheapest option, though it does come with some potential downsides. Manufacturers extract this salt from underground salt concentrates, so it often includes other minerals and associated impurities. Some rock salt is contaminated with calcium sulfite, which can get in the way of your water softener’s ability to dissolve the salt and create a useful brine. This can lead to clogs and other maintenance issues down the line.

Pros

• Relatively affordable

• Easy to use

• Can also be used for de-icing

• Widely available

Cons

• Contains more impurities than other types, leading to sediment buildup

• Somewhat high maintenance

• Might not be as efficient as other salts

Solar Salt

Solar salt is a good option for most homeowners. It’s cheap—though not as cheap as rock salt—and over 99% pure. This means that it dissolves easily inside your water softener’s brine tank. As a matter of fact, many plumbers recommend the use of solar salt as it can reduce clumping in the tank. Solar salt still includes trace amounts of other minerals and contaminants, however, so some manufacturers may recommend against using it.

Pros

• Over 99% pure

• More affordable than many other types

• Lower maintenance

• Works with many softener types

Cons

• Potential for clumping in humid regions

• Not suitable for all plants

• Weather conditions can influence its supply and price

Evaporated Salt

Evaporated salt is the most expensive sodium chloride available, but it is also the purest and most efficient. Typically available in pellets and cubes, evaporated salt boasts a purity rating of over 99.9%. In other words, it won’t gum up your softener system, even with long-term use.

Pros

• Highest purity

• Low maintenance

• Consistent performance

Cons

• Expensive

• Can clump in humid regions

• Not as readily available as many other types

Potassium-Based Water Softener Salt

Photo: Kentaroo Tryman / Maskot / Getty Images

One popular water softener salt option is not salt at all. Potassium chloride has become a go-to choice for water softener systems for several reasons. It tends to work just as well as sodium chloride, integrates with most systems, and doesn't add any salt to your home’s water supply. Instead, it adds the healthy and essential nutrient potassium. This makes it a boon for many health-conscious consumers. 

However, not all health-conscious homeowners may choose potassium pellets for their water softener system. If you have kidney or other renal issues, doctors recommend a reduced potassium intake. Additionally, potassium chloride is much more expensive than traditional water softener salt options. Those on a budget may opt for good ol’ salt.

Pros

• Doesn’t add salt to water supply

• Adds potassium to the water, an essential nutrient

• Safe for most plants

• Compatible with most systems

Cons

• More expensive than many other types

• Not as widely available

• Might not work as efficiently as sodium salts in certain systems

Factors to Consider When Picking a Water Softener Salt

When selecting water softener salt, there are a few factors that can help you make the right choice for your home. For instance, if you have extremely hard water, then you’ll benefit more from salts that are highly efficient, like evaporated salt. 

Water Hardness

Not all hard water is equal. Some hard water has extremely high mineral content, which requires a pure and efficient salt, like evaporated salt, to effectively soften. If your hard water has a lower mineral content, you might not need the most efficient salt on the market. 

System Size and Type

The capacity of your water softener, which is often measured in grains per regeneration cycle, affects how much salt is required for efficient softening. Generally, larger systems need more salt per cycle, so choosing a high-purity salt, like evaporated salt, can help you limit refill cycles and reduce maintenance costs. 

Additionally, some water softening systems only work with certain types of salt. So make sure the type of system you have is compatible with the salt you’re interested in using. 

Water Usage

If your household uses quite a bit of water consistently, then you’ll need a salt that maintains its effectiveness under constant demand, which is generally high-purity salt like evaporated salt. If your home’s water usage fluctuates, then a medium-purity salt, like solar salt, is a good choice since it’s effective enough to handle some periods of high demand but more affordable than evaporated salt. 

Maintenance

Some salts lead to more sediment buildup in the brine tank, which means more frequent cleanings are required from you. Typically, high-purity salts require less maintenance than low-purity salts since they don’t leave as much (or, in some cases, any) sediment buildup in the tank. So if you don’t love the idea of frequently cleaning the tank, high-purity salt might be worth the extra money. 

Health

Salts change the composition of your drinking water, which can impact your health. For instance, sodium-based salt adds more sodium to the water, which isn’t ideal for people on low-sodium diets. Meanwhile, potassium salts add essential nutrients to the water, boosting its health benefits.  

Environmental Impact

Many salts, like sodium-based salts, leave discharge in wastewater, which can have negative effects on the environment. If environmental impact is at the top of your priority list, then your best bet is to go with a potassium-based salt, which is generally friendlier to the environment than other types. 

Salt-Free Water Softeners

A third option is a salt-free water softener, otherwise known as a salt-free water conditioner. These appliances don’t actually soften your home’s water supply. Instead, they descale water to prevent solids from depositing in pipes and water-using fixtures. They require less maintenance than traditional water softener systems, don’t require salt or potassium to operate, and last just as long, around ten years.

The downsides of a saltless system? First of all, they are expensive to install. Count on paying between $500 and $3,000 for a professional installation, whereas a regular water softener appliance costs between $100 and $1,800. Also, no-salt systems are not that effective with sitting water, such as your well or water heater. These areas can still get significant limescale buildup. 

Remember, sodium chloride, potassium chloride, and even saltless systems will all get the job done. Base your decision on your budget and any environmental or health concerns you may have.