September 08, 2022 8 min read
If you’re in the market for a salt-free water softener, unfortunately, you are out of luck. A salt-free water softener does not exist. The ion exchange process used by water softeners doesn’t work without the sodium ions displacing the calcium and magnesium ions that create water hardness. A more accurate description of units commonly marketed as salt-free water softeners would be a salt-free water conditioner or scale inhibitor. Join John Woodard, Master Water Specialist, as we debunk salt-free softeners and explore water softener alternatives.
Salt-based water softeners turn “hard” water into “soft” water through a process called ion exchange. Using the electronic metered valve mounted atop the resin tank, the system measures water by the gallon before running a cleaning cycle. Once the resin bed reaches its saturation point, the cleaning cycle begins. During the cycle, a series of backflushes purge the trapped minerals and washes them out of the system. When water flows through the resin bed inside the tank, salts like sodium and potassium chloride are exchanged with hardness-causing minerals (primarily calcium and magnesium), resulting in “soft” water. The salts are also replenished in the resin bed during the cycle and the system is ready to go again.
Salt-based softeners are designed to remove hardness-causing minerals from your water. As a result, you’ll probably notice a little to no limescale buildup on fixtures and appliances in your home. You’ll also see your clothes appearing brighter and cleaner and your hair and skin no longer feeling dry and itchy. Other long-term benefits include more efficient and longer-lasting appliances as well as fewer repairs and plumbing maintenance. But despite all these great benefits, most salt-based softeners are more expensive than their salt-free counterparts and often require regular maintenance.
Salt-based softeners are effective in softening your water and should be used if your hard water levels are considerably high.
A salt-free water conditioner is a water filtration system that crystallizes magnesium and calcium minerals prevalent in hard water. These micro-crystals are unable to leave solution and attach to pipes and water heaters in the form of scale. Water conditioners do not remove hardness minerals, they physically alter them and render them unable to form scale build-ups. Traditional water softeners eliminate hardness minerals through a process called ion exchange. In an ion exchange process, plastic resin beads are rinsed with a salt solution that charges each bead with a sodium ion. When the hard water flows through these beads, the sodium ions exchange with the magnesium and calcium ions. The water exiting the tank and into the house is now softened, but does contain low amounts of sodium as a byproduct of the softening process.
The added sodium content has led to some controversy surrounding water softeners. In reality, the amount of sodium added by water softeners is minimal and far less than popularly imagined. Salt-based softeners also go through periodic regeneration cycles to replenish the resin beads with sodium ions. This results in brine-heavy wastewater flushing into city water drain lines, which has instigated a water softener ban in some municipalities. All of this has led to a push for salt-free water softener alternatives. Unfortunately, this has resulted in misleading albeit creative marketing strategies. Water conditioners billed as “salt-free water softeners” are targetting those seeking a salt-free system, but the implication that softening occurs is inaccurate. Though these water conditioners do address some of the problematic aspects of hard water, they do not result in soft water.
Water Softening involves an ion exchange process, which removes both magnesium (Mg2+) and calcium (Ca2+) from water. During the ion exchange process, a polymer resin bed attracts hard water minerals and replaces them with sodium ions; it is this removal of magnesium and calcium that defines "water softening".
It is a common misconception that salt-free water softening systems remove hard water minerals the same way that their salt-based counterparts do. Some believe that the only difference is that one uses salt, while the other does not. In reality, salt-free water softeners DO NOT actually soften water at all – they “condition” it.
Unlike salt-based softeners which use ion exchange to remove hard water minerals from water, salt-free water softeners use a physical process known as Template Assisted Crystallization (TAC). This process converts the hardness minerals in the water to a hardness crystal that will not stick to any surface in your home. Salt-free softeners are also known as water conditioners because they do not actually “soften” the water; They condition (or neutralize) it. And because these types of systems do not trap any materials, there’s no need for a cleaning cycle to remove captured ions.
The truth is that salt-free water softeners aren’t water softeners, don’t provide many of the same benefits that salt-based systems do, and aren’t certified to meet industry standards. Here’s a breakdown of how they compare and why a salt-based system is a better investment.
Salt-free water conditioners do prevent scale from forming in your plumbing. But, with a salt-free water conditioner or scale inhibitor, you will not see many of the advantages provided by a water softener. Water softeners physically eliminate the hardness minerals from the water supply and flush them down the drain. The minerals are barred from entering your home and damaging your water heaters and appliances. However, hard water damage extends beyond just scale. Laundry washed in hard water comes out of the machine stiff with dingy coloration. Dishes washed in hard water are foggy and come emerge from the rinse streaked with soap spots. Soap and cleaning products build up in a thick scum, as hardness minerals prevent soap from lathering properly. Hard water also is miserable to shower in as it dries out skin and hair alike.
A salt-free water conditioner will not address any of these problems. The hardness minerals exist in crystallized form, but they are still present in the water. Your fresh load of laundry will still be drab and dulled and your bathroom will still be covered with soap scum stains. The only way to eliminate these headaches to soften the water. Hence, why the common trade name “salt-free water softener” is not only false, it is deceptive. Salt-free water conditioners do provide protection against scale, but to associate them with all the benefits afforded by water softening is patently dishonest.
As discussed above, salt-based water softeners utilize a negatively charged resin bed to attract and remove magnesium and calcium from the water supply. These water softeners also utilize salt to clean the water softener and regenerate the resin bed. During regeneration, positively charged sodium ions replace the hard water minerals trapped in the resin bed, and the hard water concentrate is flushed down the drain.
Salt-free water softeners, on the other hand, do not remove hard water minerals from the water. Rather, they transform the magnesium and calcium chemically, so that they do not cling to surfaces and precipitate into scale. Because the hard water minerals are not actually captured by salt-free water softener systems, there is no need for salt or a regeneration cycle to purge the minerals down the drain.
Since the very definition of water softening requires that hard water minerals be REMOVED, and the salt-free process only ALTERS the minerals, allowing them to remain in the water, salt-free water softeners are not actually softening water – rather, they are for “water conditioning”.
There are several advantages to salt-free water conditioners that set them apart from traditional water softeners.
Salt-free water conditioners are very low maintenance systems. Installation is very simple, as the systems consist of either a single tank or cartridge. Since water conditioners neither backwash nor go through regeneration cycles, they do not need drain connections. They don’t require storage tanks for regenerating brine or control valves to monitor flow and initiate backwashing cycles. They don’t require salt or potassium and rarely demand any sort of service from a plumber. They are unlikely to have a dramatic effect on your flow rate. Unlike salt-based softeners, they don’t require any electricity to operate, saving you on electric bills.
Since salt-free water conditioners do not go through regeneration cycles, they produce no wastewater. They don’t dump chlorides into the waste stream, which can be strenuous on municipal water treatment plants. They also save water since all the water processed by the water conditioner goes straight into your home or tankless heater.
The TAC media in salt-free water conditioners only has to be replaced once every three to five years. Furthermore, it takes remarkably little media to sustain an entire whole-house water conditioning system. Unlike water softeners, salt-free tanks do not need to be filled with the media. Most whole-house systems only require between 5-10 liters of media to last them several years.
If you don’t want to install a whole-house system, scale inhibitors come in a variety of cartridge sizes and flow rates. This means you can install a single anti-scale filter cartridge in front of your tankless water heater or inline with your other water filtration systems. If you want a whole house system with more extensive filtration abilities, a whole-house chlorine reduction and salt-free conditioner system is available. This will both prevent scale accumulation in your home and improve the taste and odor of your water supply. The removal of chlorine and chloramines will also protect the TAC media and prolong the life of the system.
Some people dislike the “slippery” feel of soft water. Others complain how showering in soft water can leave you feeling the soap is still clinging to skin and the shampoo never fully washes out of your hair. This is entirely preferential, but, if you adverse to the feel of soft water but still desire the removal of scale from your plumbing, water conditioners provide you with a happy medium.
Though they have their share of applications, keep in mind, there are several downsides to water conditioners.
Unfortunately, salt-free water conditioners are useless where hard water is the most common: well water. Well water is very likely to possess moderate to high levels of iron and manganese. Water conditioners are rendered utterly ineffective against iron and manganese. The iron coats the TAC media, blocking the nucleation sites that create the hardness micro-crystals. In water heavy with iron and manganese, the magnesium and calcium ions will bounce off the anti-scale media and flow into your household plumbing, creating scale formations along the way.
Again, despite the common “salt-free water softener” title, these systems do not provide soft water. Soft water alleviates the stress of endlessly cleaning up after hard water. You will still have to use double the amounts of laundry detergent and dishwasher soap to only achieve mediocre results. You will still have to clean soap scum stains out of your sinks and bathtubs. Salt-free water conditioners only have limited efficacy against very hard water.
A salt-based water softener actually removes minerals like calcium and magnesium from your water, giving you soft water. Benefits from a salt-based system include:
In terms of overall water “softening”, you’ll probably be happier with a salt-based system if you prefer a slippery feel to the water. Or if you are concerned about wasting water and adding salt back into your environment than a salt free system is the choice. Both types of systems are designed to combat the negative effects of hard water. If you are more concerned with price, a salt-free system may work for you, if you find you can’t live without that slippery feel to the water then maybe a salt based system is the answer. At the end of the day either system will eliminate the negative effects of hard water it is just preference on which technology you decide to go with.
While Culligan does not offer salt-free water softeners, we do have a collection of diverse water conditioners that will produce top quality, salt-free water. We also offer a complete line of water softeners to satisfy your water softening needs. Your satisfaction is guaranteed!