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What Is Hard Water Salt?

C. Mitchell
C. Mitchell

Hard water salt is any type of salt that has been optimized for use in a water softening system. Most of the time, it has been specially produced for softening. While hard water salt may resemble ordinary table salt or sea salt, it is usually pure sodium or potassium chloride. Softening systems use these chloride ions to remove other harsher mineral compounds from a water supply.

Water is often considered hard if it contains high concentrations of magnesium and calcium. Hard water does not usually carry any health risks, but is often quite bothersome for homeowners. Effects of hard water include mineral deposits that clog drains, scar pipes, and leave stains on appliances and cookware. Soap does not dissolve easily in hard water, either, making bathing and dish washing something of a challenge. Installing a water softener is often one of the only ways to get rid of hard water.

Hard water salt.
Hard water salt.

Most soft water filters work on an ion exchange basis that depends on the regular presence of hard water salt. These devices are generally small, and are designed to filter water from the source as soon as it enters the house. Homeowners usually install them at the site of their main water hook-up, be it in a cistern, a well, or a community line.

Salt must usually be added to a specific chamber within the water softener. As water passes through the system, dissolved salt mixes in in small concentrations. Resin beads agitate the water molecules, loosening the grip of the magnesium and calcium ions. Sodium and potassium chloride from the salt then grips the molecules, effectively replacing the hard minerals, which generally fall to the bottom of the chamber.

Hard water salt is used in water softening systems.
Hard water salt is used in water softening systems.

Softened water does not taste salty, in large part because the salt crystals are reconfigured during the exchange. The salt also enters into the water in very low concentrations. A lot depends on water usage patterns, but most residential systems need only a small amount hard water salt every month. Replacing salt is usually as easy as adding a measured amount to the device’s salt chamber.

There are several types of hard water salt on the market. Most are sold through appliance or home repair shops. It is sometimes possible to use ordinary rock salt or table salt in commercial softeners, but the water treatment results are not always as good.

Salts that are designed specifically as hard water salts are usually very concentrated, and do not have any additives. They are also usually highly water soluble, which means that they are designed to dissolve quickly and evenly. Homeowners who use more standard salts may get clogs as non-dissolved particles mix with filtered hard water substrate. If a salt’s ions are not easily detached, it may not prove tremendously effective in a softening system, either, as hard water molecules find their way through.

Using salt for hard water is one of the most effective ways of lessening the occurrence of hard water spots and stains and promoting a more balanced, less abrasive water supply. The salts should only be used in salt-approved softening systems, however. Simply adding salt to a water supply will not do anything to counteract mineral content, and salt can actually do damage to a non-salt filter.

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    • Hard water salt.
      By: Jiri Hera
      Hard water salt.
    • Hard water salt is used in water softening systems.
      By: Photographee.eu
      Hard water salt is used in water softening systems.