How To Calculate The Salt Needed For Your Water Softener

How To Calculate The Salt Needed For Your Water Softener. Everyone's water varies in hardness and all water softeners are unique. This article helps determine how much salt your water softener needs.

Water softeners are essential appliances for people living in hard water areas. They work by removing minerals, such as calcium and magnesium, from the water, which can cause limescale buildup and other issues. However, to function properly, water softeners require salt, which needs to be added to the system periodically. But just how much salt does your water softener need?

Generally, the larger the unit and the harder the water, the more salt will be required. But various factors such as overall hardness of your water and softener tank size will vary the amount of salt needed.

By determining the right amount of salt to add, you can ensure that your water softener is functioning properly and providing you with the best quality water possible.

Understanding Water Softeners

A water softener is a device that removes minerals, such as calcium and magnesium, from hard water. Hard water is water that contains high levels of dissolved minerals, and it can cause problems such as scale buildup, decreased efficiency of appliances, and dry skin and hair. Water softeners are commonly used in households and businesses to improve the quality of their water.

What is a Water Softener

A water softener is a device that uses a process called ion exchange to remove minerals from hard water. It consists of a resin tank, a valve, and a control system.

The resin tank contains resin beads that attract and hold onto the minerals in the water. The valve controls the flow of water through the tank and initiates the regeneration process when necessary.

The control system, which can be manual or computerized, manages the operation of the valve and monitors the efficiency of the system.

Types of Water Softeners

There are two main types of water softeners: salt-based and salt-free.

Salt-based water softeners use resin beads and salt to remove minerals from the water. These types of water softeners are more effective at removing minerals, but they require regular maintenance and the addition of salt.

Salt-free water softeners use a process called template-assisted crystallization to convert minerals into crystals that are too small to adhere to surfaces. Salt-free water softeners are low-maintenance, but they are less effective at removing minerals.

Salt Based Water SoftenerSalt Free Water Softener
Use Resin Beads and SaltUse template-assisted crystallization
More EffectiveLess Effective
Require Regular MaintenanceLow-Maintenance
Table showing info of different types of water softeners

How Water Softeners Work

Water softeners work by exchanging ions in the water. The resin beads in the tank have a negative charge, which attracts positively charged minerals, such as calcium and magnesium. As the water passes through the resin tank, the minerals are attracted to the resin beads and are removed from the water.

When the resin beads become saturated with minerals, the valve initiates the regeneration process. During regeneration, a brine solution is used to flush the minerals from the resin beads and recharge them with sodium ions.

The minerals and brine solution are then flushed out of the system, and the resin beads are ready to remove more minerals from the water.

Water softeners vary in efficiency and resin volume, which affects how often they need to be regenerated. Some water softeners use a computer-controlled valve, such as the Logix valve, to monitor the efficiency of the system and initiate regeneration only when necessary. This improves the efficiency of the system and reduces the amount of salt and water used during regeneration.

Water Softener: Calculating The Salt Needed

When it comes to water softeners, one of the most important aspects is ensuring that the proper amount of salt is used. This can vary depending on a number of factors, including water hardness, capacity, and salt setting. Here’s how to calculate how much salt you need:

Determining Water Hardness

The first step is to determine the hardness of your water. This is typically measured in grains per gallon (GPG). You can find this information by contacting your local water utility or purchasing a water hardness test kit.

The national average for water hardness is around 10-12 GPG, but some areas may have very hard water with levels as high as 20 GPG or more.

Calculating Capacity

Next, you’ll need to determine the capacity of your water softener. This is typically measured in cubic feet and can be found in the manufacturer’s instructions or by contacting the manufacturer directly. If you’re unsure, a general rule of thumb is to assume a capacity of 1 cubic foot per person in the household.

Calculating Salt Setting

Once you know the hardness of your water and the capacity of your water softener, you can calculate the salt setting. This is the amount of salt needed to regenerate the resin in your water softener during the regeneration cycle. A common salt setting is around 15 pounds per cubic foot of resin, but this can vary depending on the specific water softener and the level of water hardness.

Calculating Salt Usage

Finally, you can calculate how much salt you’ll use on a regular basis. This will depend on your water usage and the frequency of regeneration cycles. A typical household will use around 80-120 pounds of salt per month, but this can vary depending on factors such as water hardness, iron content, and salt levels in the brine tank.

Remember to monitor salt usage and adjust as needed to ensure that your water softener is functioning properly and providing softened water.

Types of Water Softener Salt

When it comes to selecting the right salt for your water softener, there are several types to choose from. Each type has its own unique characteristics that make it suitable for different situations. Here are the most common types of water softener salt:

Rock Salt

Rock salt is the most basic type of salt used in water softeners. It is mined from underground salt deposits and is the least expensive option. However, it contains high levels of impurities and can leave a residue in your brine tank. This can cause your water softener to work less efficiently and require more frequent cleaning.

Solar Salt

Solar salt is made by evaporating seawater or brine in large outdoor pools. It is a purer form of salt than rock salt and is less likely to leave residue in your brine tank. It is also less expensive than evaporated salt, making it a popular choice for many homeowners.

Evaporated Salt

Evaporated salt is the purest form of salt used in water softeners. It is made by boiling brine in a vacuum chamber, which removes impurities and leaves behind pure salt crystals. While it is more expensive than other types of salt, it is also the most effective at keeping your water softener running smoothly.

Block Salt

Block salt is a convenient option for those who don’t want to deal with bags of loose salt. It comes in the form of large blocks that are placed in your brine tank. While it is more expensive than other types of salt, it is also less messy and easier to handle.

Crystal Salt

Crystal salt is a high-purity salt that is used in some water softeners. It is made by evaporating brine in a controlled environment, which produces large, pure salt crystals. While it is more expensive than other types of salt, it is also less likely to leave residue in your brine tank.

Maintaining Your Water Softener

Proper maintenance of your water softener is essential to ensure its longevity and effectiveness. Here are some tips on how to maintain your water softener:


Regular maintenance of your water softener is crucial to keep it functioning correctly. It is recommended to have your water softener inspected annually by a professional. During the inspection, the technician will check the resin bed, clean the brine tank, and ensure that the autotrol is functioning correctly.

Additionally, it is important to check the salt level in the brine tank regularly. The salt level should be maintained at least half-full to avoid salt bridges. A salt bridge occurs when a hard layer of salt forms on top of the salt in the brine tank, preventing the salt from dissolving and regenerating the resin bed.

How to Conserve Water Softener Salt

Conserving water softener salt not only saves money but also helps the environment. Here are some tips on how to conserve water softener salt:

  • Reduce your daily water usage by fixing any leaks, taking shorter showers, and turning off the faucet when brushing your teeth.
  • Use a salt dose that matches your daily water usage. The USGS recommends 1 pound of salt per 1,000 gallons of water.
  • Consider using a salt-free water conditioner if you have a large family or well water with high levels of dissolved iron.
  • Regularly check the resin bed and clean it if necessary.
  • Choose a salt-based water softener with a shorter regen cycle to reduce salt usage.


Hi, I'm Chris. Who knew there could be so many interesting things about salt?!

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