Salt-Based Vs. Salt-Free Water Softeners

You may already know what a water softener is: a device that removes the excess of dissolved salts in a water supply (mainly calcium and magnesium) to make it more appropriate for human use, improving its efficiency for washing, cooking, bathing and cleaning. There are however two different types of water softeners: salt based and salt-free water softeners.

There is another type of water softening device in the market: magnetic water softeners. These devices use a powerful magnetic field to change the conformation of the dissolved salts in the water, rendering them temporarily harmless (for about 48 hours). But these are not true water softeners as they do not remove the dissolved salts, they just delay its harmful and negative effects, so these are considered water conditioners, so we will not include them here and we will not discuss them here.salt-vs-salt-free

But back to the true water softeners; each one has its own different mechanism of action through which it removes the hardness in water. Let’s go into detail with both systems:


Salt-based systems

Salt-based water softeners have two main components: a brine tank and a resin tank. The resin tank is filled with resin beads that strongly attract salt ions; the brine tank is a tank that holds common salt (sodium chloride) that is replenished by the user, the salt is then mixed with water so that the water softener can start using it.

The resin beads are bathed in the brine and, as they attract salt ions, they get filled with the sodium ions from the brine bath. However, keep in mind that the sodium ions are not very strongly attached to the resin beads, at least not as strongly as other ions.

After the resin beads are filled with sodium ions, water is run through them; hard water is filled with calcium and magnesium ions, and since the sodium ions bind weakly to the resin beads, and the other salts are strongly attracted to them, then the calcium and magnesium ions displace the sodium ions and take their place in the resin beads. So, the following change takes place in the water once it has gone through the resin filter: the calcium and magnesium ions are trapped and removed by the softener, and the water loses its calcium and magnesium and is left just with the sodium ions. So the sodium salt is left in the water but that salt is harmless and has none of the negative effects of the other salts. This technology is called Ion-exchange.

These types of systems can be easy to install if you have the correct information.


Salt-free systems

A salt-free water softener works somewhat differently to a salt-based one: using a different new technology called Template Assisted Crystallization; salt-free water softeners rearrange the molecular structure of the salts: turning them from salts into crystals, which are harmless and do not have any of the harmful effects of salts, and so the water still keeps its contents of calcium and magnesium, but none of its negative effects and properties. So, in a way, you can see that the new salt-free water softeners do something similar to magnetic water conditioner, and while both change the molecular arrangement of salts in water and do not remove anything, the changes a magnetic water conditioner are temporary and only last 48 hours, which means that if water treated by a magnetic water conditioner sits in a single place for too long (like inside a water heater) it will revert to its previous harmful form eventually and still form scales. The changes created by a salt-free water softener on the other hand, are long-lasting, virtually permanent.


Which one is better?

Both systems have its detractors and its supporters, and opinions are very polarized: those who like salt-based systems, swear by it and would never use salt-free systems and vice versa.


Advantages of both systems:

Salt-based water softeners Salt-free water softeners
·    Truly get rid of harmful salts

·    Give water a “cleaner” feeling

·    Are better for skin, nails and hair

·    You use less soap and detergents

·    Will fix even the hardest water

·    Leaves sodium on water (which may not be good for some for medical reasons)

·      Will not require salt

·      Consumes less electricity

·      Creates no waste

·      Consumes no water

·      Has no regeneration cycles

·      Is more environmentally friendly


Disadvantages of both systems:

Salt-based water softeners Salt-free water softeners
·      Requires a constant supply of salt

·      Consumes more electricity

·      Creates waste

·      Wastes more water

·      Needs periodic regeneration cycles

·      Less environmentally friendly

·      Does not really get rid of harmful salts

·      May not be better for skin, nails and hair

·      Water will not “slick” or “clean”

·      May not help with harder water

·      Filter cartridges still have to be replaced

·      If you have sediments you’ll need to replace filters more often

·      Cartridges and replacements can be very expensive


If you have a problem with water hardness, you will have to first do some research on all the available options and decide which will fit best the needs of your household. Perhaps, the most important aspect to consider before buying a water softener, are the reviews and ratings of other users, read what others have to say and what think about the unit you have in mind.