Whether you’ve just purchased a water softener or have been using one for a while, once you notice the salt in the brine tank has started to run low, you’ll be faced with a decision of what salt should be used to refill it. When you start shopping for softener salt, you may be a little overwhelmed by the myriad of options. From blocks and rocks to pellets and crystals, which is the best choice. Should you be looking for evaporated or solar salt pellets? Or should you even be buying salt and choose potassium chloride? This can leave anyone feeling confused, so here we will explore what salt is best for your water softener. 

Salt Options 

The first decision you need to make is choosing between salt and potassium chloride. Most models of water softener or conditioner can work effectively using sodium chloride or potassium chloride. Both of these are actually types of salt, but we’ll look at what is commonly referred to as salt, sodium chloride. Softener salt is typically available in three forms; crystal, pellets or block salt. Salt pellets are more readily available and tend to be less expensive compared to potassium pellets. Unfortunately, the decision gets even more complicated, as there are also different types within each of these categories.

Evaporated pellets offer the highest purity rate and tend to be the most expensive. High levels of salt impurities can create an accumulation inside your softener, compromising performance and increasing the risk of repair issues. With a high purity rated pellet that is 99.9% pure, there is less chance of “mushing” or “bridging” that will require cleaning out the bottom your tank frequently.

Solar pellets are made using evaporated sea water. While solar salt tends to be more soluble compared to rock salt, it may not be as effective as evaporated salt, particularly if you have a very high water hardness level.

Rock salt looks like small pebbles or rocks. This is a cheaper option, but it tends to contain high amounts of calcium sulfate that doesn’t dissolve well and can cause maintenance issues.

Block salt should only be used if your water treatment technician has recommended it and you will need to raise the brine tank water level to ensure the block is fully submerged.  

Potassium Chloride 

The final option for your softener is potassium chloride. This can be used in place of sodium chloride to regenerate your softener resin. Potassium chloride is actually 99.9% free of sodium, so it is preferable for those who need to monitor or reduce sodium intake. Unfortunately, potassium chloride is usually only available in pellet form, and it is harder to find. Additionally, this type of pellet is more expensive. If you do decide to switch to potassium chloride, you may need to increase the dosage settings on your softener by up to 10% to ensure that the resin is properly regenerated.  

If you’re still unsure about the type of salt you should be using in your water softener, it is a good idea to speak to your water treatment technician. An experienced professional can assess your water treatment system and recommend the salt product that is best suited to your particular needs. 

With more than 25 years experience in the residential and commercial water treatment space, Terry is a WQA (Water Quality Association) certified water specialist, LEVEL 3, as well as a WQA certified sales representative.  Terry currently sits on EcoWater Systems (a Berkshire Hathaway Company) national Peers committee, as a water treatment expert advising other water professionals with less experience on best trade and technology practices. EcoWater Systems of Nebraska is one of the biggest water treatment and water delivery businesses in the state.