How Do Salt Based Water Softeners Work?
Salt based water softeners work according to a process called ion-exchange. This basically means that positively charged hard water ions in water(Ca+ and Mg+) are exchanged with a negatively charged ion and removed from water.
The positively charged ions are introduced via ionic resin beads which are coated with Sodium ions, usually. As water flows over the surface of the beads, the ion-exchange process takes place.
Over time, as the sodium levels get depleted, more salt has to be added.
How Are Salt Based Water Softeners Tested and Evaluated?
Salt based water softeners are tested according to NSF/ANSI Standard 44 that certifies, primarily their efficiency based on how much salt and water they use to regenerate.
Salt efficiency is calculated in terms of how much hardness is removed by each pound of salt, and water efficiency by how much water is required to regenerate the system.
‘Regeneration’ is basically, the process of flushing out waste, brine solution and adding more salt to the water softener. The lesser brine produced as waste and salt required to regenerate, the more efficient the softener is.
Do Salt Free Water Softeners Really Work?
First of all, let me make something clear here:
All water softeners are salt based. There are no water softeners that do not use salt. Anyone who tells you otherwise is trying to trick you with marketing jargon.
What are commonly known as salt free water softeners should be called ‘salt free water conditioners’ instead. This is because they don’t remove hard water minerals from water, they only condition the minerals so that they don’t stick to surfaces.
In other words, the hard water minerals won’t form limescale inside your plumbing, water heaters, etc or form residues on your clothes and dishes. Instead they’ll just get drained away with the water.
However, salt free water conditioners aren’t for everyone as they only work well upto a level of water hardness, over which it’s better to get a water softener.
Salt free water conditioners are mostly used in industrial settings or in wineries and breweries which need water that won’t form scales and damage their expensive equipment. So, if you’re an average homeowner, should you buy one?
According to me, it makes sense to buy a salt free water conditioner when:
- You already have a RO filter installed for drinking purposes
- You don’t mind the taste of hard water but want to reduce limescale formation around the house
How Do Salt Free Water Softeners Work?
There are mainly two technologies in the salt free water conditioner market:
- Template Assisted Crystallization(TAC)
- Magnetic Softeners
Template Assisted Crystallization(TAC):
According to HPAC Engineering, here’s how these systems work in a nutshell:
TAC water softeners consist of resin beads which cause the dissolved hard water minerals in water to aggregate and form crystals on the surface of these beads. Once they’re big enough in size, the seed crystals detach from the beads and flow along in the water, further attracting other hard water ions.
These crystals don’t stick to any surfaces and flow along in water, and eventually- straight down the drain.
Here are some advantages of a TAC water softener:
- Does not require electricity
- Does not cause any noticeable drops in water pressure
- Average lifetime of the resin media is about 3 years and does not depend on the hardness of water or the volume of water processed
Magnetic Water Softeners:
Magnetic water softeners are a very controversial product. While a lot of people claim to have benefited, there is almost no science behind the product. It seems almost too ludicrous that such products, which claim to ‘reduce limescale formation through electromagnetic waves’, are still on the market.
Especially when they have no conclusive tests or certifications to back up their claims. There are a lot of studies that have found that magnetic water softeners do not make any difference to your water, such as studies by:
However, a lot of consumer reviews, such as these on Amazon, are somehow positive! They even seem like legitimate, in depth reviews. I won’t say I am not confused that so many people have found a magnetic water softener useful. Feel free to check out the most popular one- Eddy Electronic Descaler on Amazon, if you like. I still won’t recommend it though.
How Are Salt Free Water Conditioners Evaluated?
They aren’t. Simple as that.
That’s because there are no industry standards as of now for measuring the efficacy of a Salt free water conditioner.
Your salt free water conditioner system could also include other filters that remove chlorine, chloramines, iron, etc from water, and it may have certifications regarding those extra filtration stages. Like I said though, do not confuse them as certifications for your salt free water conditioner.
Advantages and Disadvantages of Salt Based Water Softeners
- Actually soften water, i.e: remove hard water minerals. Salt free water softeners do not
- Reduce limescale formation
- Better sudsing- i.e lather formation from soap
- Good for hair and skin- Showering in hard water is known to cause skin and scalp dryness, rashes, hair loss, and acne(Read more about it here)
- Recurring cost of buying salt
- Not eco-friendly. Produces salt water brine as a waste by-product that can possibly pollute nearby lakes, rivers, and are hard to remove from wastewater
- Some people complain of a ‘slicky’ feeling from showering in softened water due to the sodium/ potassium salts
Advantages and Disadvantages of Salt Free Water Conditioners
- Require just one change in filter media every 2-3 years- independent of the hardness and volume of water processed
- Reduce limescale formation
- Eco friendly- no salt water discharge
- Does not actually soften water. Just conditions hard water minerals to not stick to surfaces and form limescale
- Starts becoming ineffective as water crosses a particular threshold of hardness
For most, I recommend getting a salt based water softener because you get the full solution- less limescale formation as well as lower levels of hard water minerals in your water.
In case you’re on a low sodium diet, you may want to consider using Potassium salts instead of Sodium in the water softener. Also, some people experience itching and skin irritation from showering in softened water- because they are allergic to the salt used. If you think you might be allergic, consider changing your salt as well.
Salt based water softeners are quite expensive and have considerable maintenance costs and well. So you definitely should do your research before buying one.
You may want to check out the Fleck 5600SXT on Amazon– it’s the most popular water softener online. If you have some DIY plumbing experience you could install it yourself, or simply call a service professional.