Salt Water For Hot Tub Sanitizing? Things to Know Before You Decide

The Rest Of the Story

Here’s the rest of the story about using salt water systems for sanitizing your hot tub. Salt water systems are being promoted as the better way to keep hot tub water clean because allegedly:

1. They require less work because it’s automated and “hands free”.

2. They don’t depend on harsh chemicals like chlorine, bromine or spa shock

3. They use an inexpensive salt like table salt instead of 
expensive hot tub chemicals

4. They leave your skin feeling better because they don’t have harsh, traditional sanitizers

5. They are environmentally friendly because they use less chemicals

6. They use diamonds in the system to create powerful cleaners

Now, don’t get me wrong. Salt water hot tub sanitization can be beneficial if you are willing to understand the reality of the system. So, lets peel back the “hype” and look at the reality by examining each of the above claims.

Claim 1, less work: They require less work because it’s automated and hands free. The simplest answer to this claim is to look at one major hot tub manufacturer’s salt water sanitization manual.
The manual has 16 pages and includes 167 separate warnings, procedures and descriptions. This means that there is a huge amount of work required to operate and maintain this system. That manual is also full of dozens of required actions, making it much less “hands free” than traditional sanitizing. This includes fun things to do in maintaining a salt water system like removing the “cell” and cleaning it in an acid solution every three months, then reinstalling it.

Claim 2, no harsh chemicals: They don’t depend on harsh chemicals like chlorine. Well, they use salt and water to constantly produce five harsh chemicals in your hot tub water as you use the tub. Their main “powerful cleaner” is in fact good old chlorine. Salt water system manufacturers also recommend that you use normal spa chlorine and spa water shock any time that the tested chlorine level gets low…which can be frequently. So much for not using “harsh chemicals”.

Claim 3, inexpensive to use: It’s true that special hot tub salt is a little less expensive than hot tub chlorine ($7 a month for hot tub salt vs. $15 a month for hot tub chlorine). But, the salt is a very small factor in the overall salt water system cost. Here are the real costs:

1. Stand alone salt water systems: $500 to $700 to purchase and only a one year warranty.

2. Built in salt water systems: Up to $1500 and only a one year warranty. Sometimes the salt system is thrown in for “free” with the purchase price of the hot tub. Nothing is “free”. Wouldn’t you prefer a $1500 cash discount instead?

3. Cells have a 1.6 year average life and cost from $300 to $500 each time one is replaced.

4. Salt water system users also have to purchase:
• Hot tub chlorine
• Hot tub shock
• Special calcium remover
• PH up and PH down
• Stain and scale defense
• De-foamer
• 5 way test strips

So, over five to ten years, the salt water system users will save a little on the salt, but overall they will spend thousands of dollars more on water sanitization than traditional hot tub chlorine or bromine users.

Claim 4, skin feels better: It’s true that a little salt in the water will not affect your skin. However, the salt water system uses a special “cell” to generate elemental oxygen, chlorine and several other “powerful” cleaners and oxidizers. Your skin reacts to these powerful cleaners and oxidizers just like it will react to hot tub chlorine. Whether its salt water generated oxidizers or hot tub chlorine, having too much of either will not be beneficial to your skin.

Claim 5, they’re environmentally beneficial because of less chemicals: It’s true that when the 167 cautions and procedures for salt water sanitization are regularly and carefully followed, less harsh chemicals will be used . Similarly, if the simple procedures for using regular hot tub sanitizers are followed, much less harsh chemicals will be used. Oh by the way, the salt water system constantly uses electricity and requires the manufacturing of non environmentally friendly components that have to be thrown out on a regular basis.

Claim 6, diamonds are used in the “cell”: Not really. Just a diamond vapor is deposited in the “cell”. And, after the “cells” fail, they’re thrown in the trash. Not much diamond value after all.  Apparently, diamonds are referred to as a way to make the salt water systems appear more valuable.

The bottom line: Sadly salt water sanitization systems for hot tubs are over ”hyped”, making consumers confused. They are in fact, complicated to operate properly, expensive to purchase and maintain, create harsh oxidizers and have no special environmental advantages.


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30 Responses to “Salt Water For Hot Tub Sanitizing? Things to Know Before You Decide”

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  1. Rich s says:

    I fell like I was ripped off when I bought the ace salt system for my envoy hot tub . I was never told that the salt generator only last about a year an a half. The replacement cost will be over 900. Dollars it’s been over a year now and every time I look at my spa putting chlorine into my tub it just burns me.

  2. Gary Mumma says:

    Thanks for the tips on salt water hot tubs. You have helped me to decide if I want to change to salt water or not.
    The answer is a definite ▲”NO”

  3. Kathy Shaw says:

    My secretary at work said she had to quit using her hot tub because of her asthma. She went to a friend’s who suggested they get in the hot tub. She declined, but they told her it was salt treated, so she got in. She said she had not problems with her asthma. She knows I’m just starting to look at tubs, and that I have asthma. Any truth to this?

    • Fireside says:

      “Salt water” hot tubs simply use a complex process to generate and maintain a chlorine sanitizer from the salt which is part chlorine and part sodium. The needed active chlorine sanitizer is the same, regardless of its source. Many hot tubs already use a chlorine compound additive as the chlorine source.
      There is no known cure for asthma that comes from dilute chlorine/water immersion. If there were, it would be well known by now. We’re not medical experts, however 30 minutes of breathing the warm vapors from any hot tub could have temporary effects on the throat and lungs.

      • Marie T-C says:

        When chlorine reacts with organics, it creates by-products that are toxic and irritants. In a saltwater chlorine generator, the reactions happen in the chamber and then when the water comes out, the overwhelming majority of the chlorine converts back to salt and therefore your lungs are not irritated. That’s why your friend’s asthma is not triggered. It is of course not “cured”, although using a spa may help her overall health.

  4. Chris BC says:

    OK, I’m with you on the diamond hype. But, tell me how a salt water spa is going to be vastly different from my salt water pool. In 2 years in my salt water pool:

    1. No added chlorine
    2. No shocking ever, other than letting the salt cell run continuously for 8 to 10 hours if the chlorine level gets low.
    3. No calcium remover, ever. And of course if you use soft water you shouldn’t need to remove calcium. I used some soft water to fill my pool because it does need some calcium for the pebble tech surface.
    4. Only pH down, mostly via adding liquid acid which is not that expensive and is only needed once a month or so during swim season.
    5. No “stain defense” or “scale defense”. Again soft water or partial soft water will avoid scale buildup.
    6. No de-foamer. I could see where this would be very different in a hot tub with the jets running.
    7. Test strips are cheap and are a good idea for all pools and spas.
    8. I’ve only needed algaecide one time after a dust storm turned the pool brown and muddy. (Life in the desert problems.)
    9. Cleaning the salt cell with the same acid I pour in the pool (Muriatic acid) is very simple and easy.

    Otherwise the chlorine odor is almost nil, which can’t be said of standard pools, and the water is always clear unless stuff has blown into it. If I can get this in a hot tub why not?

    Clearly the salt cell dying every 12 to 18 months would be a huge negative, but aren’t there other alternatives? My Hayward salt cell for my pool is at least 3 years old and maybe more.


    • Fireside says:

      Our statements are based on the words taken directly from the hot tub industry’s largest “salt water” hot tub maker’s manual for their “salt water” hot tubs.
      Additionally, swimming pool water chemistry is totally different than hot tub water chemistry. The reason for the difference is two fold. 1. Hot tubs operate at 102F and not 70F. That temperature difference creates dramatically different chemical needs. 2. Hot tubs have about 300 gallons of water and pools have 10,000 to 30,000 gallons of water. This massive volume difference also creates totally different chemical needs.

  5. Cory AZ says:

    The opinions provided by the author does not match my real experience. Salt systems are not complex, but since they only produce chlorine (sanitizer), you may still have to maintain your spa with other products as needed. What a salt system does is help you maintain a proper chemical balance at all times so you don’t have to continually add other chemicals as you struggle to achieve a proper water balance. I have found that, overall, less chemicals are needed and that I need to use shock less often. The downside is cost. Salt cells are relatively expensive and do need to be replaced. A good quality cell will last 3+ years. Personally, I think the salt systems are worth the money for the easy maintenance they provide.

    • SpaSyl says:

      What brand of salt cell would you consider “good quality”? I am in the market to purchase a spa and want to use fewer chemicals

    • Fireside says:

      Thanks for your comments Cory.
      Here are the reasons that hot tub salt water sanitization systems are much more complicated for most people to use than traditional sanitization systems. This is taken from the salt water sanitization manual that comes with the industry’s largest hot tub manufacturer and salt water sanitization system provider:
      1. The manual has 16 pages and includes 167 separate warnings, procedures and descriptions. This means that there is a huge amount of work required to operate and maintain this system.
      2. That manual is also full of dozens of required actions, making it much less “hands free” than traditional sanitizing.
      3. Then there are required “fun things” to do in maintaining a salt water system like removing the “cell” and cleaning it in an acid solution every three months, then reinstalling it.
      Certainly a consumer can ignore all the above and do little to operate their salt water system in accordance with the manufacturer. The likely result is poor sanitizing and regular replacement of the 1 year warranty, $800 salt cell that makes the system work.

      The more traditional sanitizing systems are much simpler to use properly and less expensive to maintain.

  6. Pdoumas says:

    I think Cory’s arguments are excellent. I would be very interested to have a side-by-side similar comparison of a manual from a traditional spa, to compare to your so-called overly complicated manual accompanying a saltwater Spa. At this point, I feel like you have not backed up your argument with any facts, or sources. And, by sources I don’t mean vague references to in some unknown manual. Link? The manual for my car has 300 pages, but I feel like it’s maintenance is pretty easy. Just the number of pages or pictures of a manual is not evidence enough to support any argument against one type of thing or another. Please elaborate, oar lose any shred of credibility you have left.

  7. Pdoumas says:

    At $320 it is a bit expensive, but this unit has titanium plates, which are cleanable. No replacing cartridges year after year. Pretty affordable, considering some of the benefits that the salt water provides. My skin always feels better after a saltwater soak… There were some other cheaper systems to, but this one seemed like probably the best deal for aftermarket fitment to existing spa…. Happy soaking!

  8. Coffebrk says:

    This is a confusion article with which I disagree based on my personal experience. I have had a Jacuzzi Spa for the last 10 years setup with fresh water and a chlorine/bromine sanitizer. About 1 1/2 years ago I converted it to salt water and couldn’t be happier. Here is my experience:

    1.Yes , salt is less work. No chemicals other than the initial salt charge and PH down to adjust maybe every 3 months. The chlorine level with my Solazz generator has remained steady within a range on .08 to 1.2. We use the spa approximately every other day sometimes more on a weekend. I have added 1 cup of salt 2 months ago to bring the level up to 3500 ppm from 2800 ppm. The water is still crystal clear and I am seriously thinking of keeping it for another summer. There is no odor at all.
    2. The original manual that came from Jacuzzi when new had 28 pages with most of them being Gov required disclaimers and safety instructions. Yes we all know water and electricity don’t mix and can kill. That was for a fresh water setup.
    3. Yes skin does feel smoother and silky after a salt session. This is not only my opinion but everyone else that uses my spa.
    4. The Chlorine generator cost me $210 and is going strong still after 1 1/2 years. If it breaks I will get a new one for about $169 from Amazon and be ahead of the game. The instructions say that the polarity reverses automatically to purge the generator plate so cleaning is not required. When using fresh water, chemicals cost me about $300 a year.
    5. I don’t buy the totally different chemical needs for a pool versus a spa. They both require sanitized water to prevent problems for humans. The spa needs a slightly higher level of sanitation due to the higher temperatures of the water and ability of pathogens to propagate faster at higher temperatures. The salt water itself prevents many of the typical fresh water pathogens from existing.

    Bottom line for me and my family: We have used both fresh and salt water in the spa and and salt works best for us. Less work, lower cost, and better skin.

    • Shannan says:

      @ Coffebrk

      Which chlorine generator do you use?

    • Shannon says:

      Thanks, Coffebrk!! I knew that somehow we could get away from the toxins, and you have greatly encouraged me.

    • Cpt says:

      I have had my hot tub since jan 2015, I dissolve about 6-7 pounds of Dead sea salt to the 350 gallon tub, I use a digital PPM tester to keep the salt between 2000-2500 PPM, an over the tub chlorinator makes chlorine from the by-product of sea salt, once in a while add spa up, NON chlorine shock as needed, and rinse the filter bi-weekly, clean the chlorinator soaking in vinegar for 30 min. about 2 times a month, thats it, dead sea salt is very easy to use and feels SO SILKY on the skin. Happy Hot tubing.

    • Dana says:

      I have a Jacuzzi as well how did you convert it to salt. I was told I can’t?.

  9. Lee Buskey says:

    I find most of this article to be totally biased, and makes horrible arguments. The expense of salt is negligible.. Not $7.00 a month. $7.00 buys 40lbs of salt. If you don’t have a salt water pool, that will last YEARS for a spa. In fact, for me, because my pool is salt water, all I have to do when its time to change the tub water, is drain it, and fill it from the pool. Already has chlorine, already has stabilizer, and is already balanced. It is easier, it does take less time, You do use less harsh chemicals, because you aren’t handling Chlorine anymore. Doh.. Yes you still need to shock from time to time, but they never say NO harsh chemicals. I don’t have track an annoying floater with tablets in it. I just installed a external salt generator for less then $200.00. Replacement cell is approx. $80.00. No idea how long it will last, but as loing as it’s a year, it’s still a deal. Personally, my skin can’t tolerate Bromine at all anymore, but the chlorine doesn’t give me any trouble. My salt water system manual is only about 4 pages, and honestly, the size of a manual is hardly an effective way to gauge the use of a product.

  10. Charles Baird says:

    This article has such a strong advisarial tone to it that I feel compelled to find out what the “they” so frequently referenced, have to say. Clearly the author has an opinion regarding the topic and this thoroughly undermines the value of the information. I was glad to see some information from people who have had positive experiences with saltwater systems.

  11. Matt says:

    Much of what you say here is very true, but only discusses one type of salt water system (a chlorine generator system). What about the better choice, a Dead Sea Salt Water system that uses sodium bromide to produce bromine instead of table salt to produce chlorine? Bromine is MUCH better for hot water than chlorine, the system warranty on a BLU FUSION bromine generator is three or five years depending on the model, they cost half as much for a plumbed-in system as what you talk about, and the water feels absolutely AMAZING. Oh, and there really is a lot less work involved, I only drain my tub once a year and don’t have to buy a bunch of other chemicals. Oh, and incidentally, the corrosion issues with sodium chloride salt are not an issue with sodium bromide salt (I use TRU BLU Salt from the Dead Sea).

  12. Ana says:

    the only reason I was looking at this system is, because the damage that brome chlorine play in our lives, by disrupting the iodine in the human body, ppl need to be informed why we are in the hope we are just look at this Google iodine disrupters or robbers, you will look at your life a different way,, bromide is use to kill insects termites and we rat it in commercial bread flours has it, iodine is essential, to our health, our thyroid gland runs on it, our uterus demand it mental development in fetus, our intelligence depends on it, and we are totally unaware of this, obesity number one cause. There is much to learn, and avoid,
    Many people ask so how to we live in this age, well we go back in time, and we make our own everything, there are many sources of essential materials out there for us to grind prepared, and feed our families without all this no sense slow killers that enter our body. I think water would be better in a pool with a light system and sir oxigenator, that way bacteria would not have the chance to live in the water, an aerobic action would be making alive. I made an experiment, water clean and all but enclosed, no pump no nothing, boy that water was the most stinky off all wasters, the other just bubbles and pump running, sun light the water kept clean, no water bugs and no odor.
    How we can get rid of chlorine bromides and this harmful chemicals that we have in everyday life, our water well city water full of chlorine, tooth paste, dental treatment whiteners etc. we may just all get real sick and die, the worst is our children the inherent of our culture have a bleak future.

  13. arthur faraday says:

    it seems to me fireside sells chemicals for hot tubs standard chlorine hot tubs require more chemicals then salt systems i keep my pool at 98 degrees and havent had to add anything but salt when required and that is not very often i have the water tested regularly by my pool supply store i beleive there is more money to be made selling chemicals rather than salt systems

  14. Michel Lyna says:

    I’ve been using salt water system for 9 years now (Started with “Tubby Systems”) and I only have praise for salt water sanitization. In the last 3 years, I’m now running on
    and never did any kind of maintenance. I use regular cheap pool salt and use the Shock oxidizer—2-lbs-P93C43.aspx at a rate of two table spoon each time we use the spa (and we often forget).

  15. Mark G. says:

    Morning, I have a 2012 Envoy HotSprings Spa. My spa eats the cells with this system. 3 yrs old and going on 3rd rod. Manual says 14000 hrs. –that’s 1.9 months. I get between 8 or 9. At 600 a new cell now that my warranty is done, well it’s ridiculous. Dealer is actually coming tonight to rip this Ace piece of crap out and going with an ozonator. H20 was nice but cell won’t last even to the manufactures specs… And at $600 for a replacement cell every 8 ot 9 months? You do the math… Very unhappy…..HotSprings was good to me though. They paid for a new ozonator minus the install. I would have liked them to pay the whole cost but they did replace 2 cells for free. Still think this system has engineering problems with how long cell lasts. They blame me, but it isn’t me… I did everything one is suppose to do to keep h20, filters clean, water is exactly where it was suppose to be.

  16. Matt says:

    This article is bogus. I own a salt water tub. After putting up with a conventional tub the day to day maintenance was awful in comparison to the salt. The water is so much better and has to be balanced way less I never need to add chlorine or shock and it maybe costs $40 to change the water which lasts way longer anyway. The problem with chlorine tubs isn’t the chlorine, it’s the acid used to stabilize the chlorine that builds up every time you dump in chlorine. Make your own chlorine…no acid, not even really a comparison. Sure the cell has a cost to replace, but wouldn’t you rather spend a big chunk of money every once in a while than spend a little money all the time? In the end the cost is a wash between the two so wouldn’t you rather be soaking in better water than standing outside of it dipping strips and measuring chemicles? It’s kind of a no brainer.

  17. James S says:

    I have been using a Saltron Mini Spa Salt System Chlorine Generator for the past 3 years, almost 4 in my Strong Spa Milan. No issues at all, the cells look great. I was told by Strong and some others it would NOT work. This is not rocket science people. Switch to salt you’ll love it

  18. Matt says:

    All read….. I have a 8 man hottub, i have not bought a saltwater system yet. I will however state that I put in salt water system on my pool 2 years ago and i will never look back!!!! Best thing I have ever done with pool, water feels awesome and skin feels great. Easy to take care of, very easy! Im guessing that whomever wrote this article is making money from chemicals. Talked with several pool guys about salt water pool and heard same crap you read hear!! Im buying salt water for hot tub don’t care if I save money, break even or pay more. If its anything like my pool it will be well worth it.

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