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Are Salt Water Hot Tubs Sanitary?

There is a lot of interest in salt water hot tubs these days because many believe they are better and cheaper to run. But are salt water hot tubs sanitary?

Salt water hot tubs are sanitary, generating chlorine from salt naturally. Because the salt converts to chlorine in minimal quality, it does not produce skin irritation usually associated with chlorine. But the water will still be completely sanitized as long as the equipment is functioning properly. 

But there is a lot more that you must know about the benefits of a salt water hot tub.

So in this article, we’ll get into how salt water hot tubs work. How to tell if they are working correctly? And if salt water is a better sanitizer than chlorine? And a lot more. 

Just keep reading to know more. 

How does a salt water hot tub work?

Salt water hot tubs work by converting salt water into chlorine through a generator. This generator contains a chlorinator cell composed of electrodes and titanium plates. When a small electrical current is passed through this cell, chlorine is created from the salt in the water. This process is known as electrolysis.

The chlorine formed by this process is natural and is released slowly into the water, so it’s less likely to irritate the skin or eyes.

There is less foam and scum build-up with salt water, so the water stays cleaner for longer. You can get by with changing the water once a year in most cases, compared to every 3 or 4 months with a regular tub.

The process also ensures a more balanced quality of water, so you don’t need to add so many chemicals to get the balance right.

You can convert your hot tub to use salt water by installing a drop-in chlorinator such as this SmarterSpa ContolOMatic, for just under $400 on Amazon.

No plumbing is required, just an electrical supply. Just click that link to see it on Amazon.

The salt is easily obtainable on Amazon – I recommend Aquasalt for around $25 for a 40lb bag, and that should last you 12 months.

Just click on the links to buy them on Amazon.

How do I know if my saltwater generator is working?

If your saltwater generator is working, your test strip will show normal chlorine levels. However, if you start getting a strong smell of the ocean or see cloudy water, that’s a sure sign something is wrong. These are signs that not enough chlorine is being produced, and you will need to check out your generator cell.

Mineral deposits can form on the plates over time, and this will need to be cleaned off to maintain the performance of the cell.

It is recommended to check this every couple of months, depending on the quality of the water in your area. With softer water, maybe not so often.

Also, depending on the model, you should get a warning on the control panel of your chlorinator when something is wrong.

The SmarterSpa ContolOMatic has chlorine detection, which indicates when things might not be working right.

It is also self-cleaning, so you shouldn’t get mineral deposits, but you will still need to check for corrosion.

After around five years, the cell in the generator will need to be replaced, which usually entails replacing the whole unit unless it is a purpose-built saltwater spa, in which case you must follow the manufacturer’s instructions.

It is not often that things go wrong, but with regular maintenance, you should get months of trouble-free use out of your saltwater hot tub.

If this is your first hot tub, you need to read this recent article on my site. It has 23 points to consider before deciding which hot tub is best for you.

Just click that link to read it on my site.

Is salt water better than chlorine for a sanitizer?

Salt water is not any better in terms of sanitizing your hot tub water compared to chlorine. The reason is that the salt water generator converts the salt into chlorine. So in that sense, they sanitize exactly the same.

The primary benefit to a salt water system is that you can kind of set it and forget it. But there also tends to be less chlorine odor and skin irritation too.

Although it may be good at sanitizing the water, regular powdered chlorine is a very harsh chemical and may cause burns and rashes if added in excess.

The tiny bubbles of gas and vapor off the water can also irritate the eyes.

When chlorine is added manually, it is always possible to overdo it if you are not used to it, and then it is a constant battle to balance the water.

But with a chlorinator cell on a salt water hot tub, the chlorine is created very slowly and only in the quantities required to keep the water clean, so there is no excess chlorine to worry about

A well-maintained salt water sanitation system will keep the water clean for up to 12 months, whereas a regular tub using chlorine has to be changed every 3 or 4 months.

So salt water may be the better option for those who don’t want too much maintenance but maximize their enjoyment.

In a recent article, I discussed the safety of saltwater hot tubs. Read more about that on my website by clicking on the link.

Can you shock a salt water hot tub?

Yes. You can and should shock a hot tub with a salt water system. However, unlike regular hot tubs, with a salt water hot tub, you can go for several weeks in between shocking without doing anything other than check pH and alkalinity levels.

Shocking is done to remove organic compounds and kill off residual bacteria, which lead to cloudy water and bad smells, usually caused by chloramines.

Chloramines occur when chlorine mixes with ammonia or other chemicals, and this can be irritating to the skin. With a salt water hot tub, this doesn’t happen, so it is not necessary to shock so often.

When you shock your hot tub, you should leave the cover off to allow the gasses to dissipate into the air, and leave the pump running. But do close off the jets, so you get a nice easy flow of water.

The amount of shock needed depends on the volume of water and the type of shock.

Always follow instructions on the packaging and carefully add the right amount of shock to the water, leaving the cover off for 20 minutes afterward. With a non-chlorine shock, you should allow 10 minutes before getting in.

But with chlorine shock, you should leave it for at least 1-2 hours.

Do I ever add chemicals to a salt water hot tub?

Yes, salt water hot tubs do still require chemicals to be added. It is a myth that salt water hot tubs don’t require any chemocals. While you don’t need to add sanitizer, you still need to check & adjust pH and alkalinity, and occasionally add shock, or else the salt water system may not function correctly.

So while it is much lower maintenance than a normal hot tub, it’s not totally set-it-and-forget-it.

I explained what to do to balance pH and alkalinity in a recent article, so if you are having problems with this, just follow the link to read it on my site.

You will need a pH decreaser and a pH increaser in stock to make sure you always have the right balance.

There are rare occasions when you might need to add chlorine to a salt water tub.

For example after a period of extra-heavy use, such as a large party or big family gettogether. That can overwhelm the chlorine generator and it might not be able to keep up.

Final Thoughts

Salt water hot tubs are just as sanitary as regular tubs because they use a chlorinator to convert salt to chlorine.

The process is slow, and only the right amount is converted, so you get the benefit of sanitization without the risk of skin irritation.

You still need chemicals to keep the water clear and safe, but much less than you would with a regular tub. But before you go converting your tub or buying a new salt water tub, you need to read my recent article where I discussed whether salt water hot tubs were better than chlorinated tubs.

Click on the link to read it on my website.

As an Amazon Associate, I may earn a small commission from qualifying purchases if you click on Amazon from my site and choose to make a purchase. You can read my complete affiliate disclosure for more details.

Jeff Campbell