Are Saltwater Hot Tubs Possible?


If you’ve gone to the beach, you have probably enjoyed the soft sand in your toes and the warm sun on your skin, among other things, but what is likely to stand out the most is the smell of salt in the air and the feeling of salty water on your body. These factors seem irreplaceable at first sight though one can’t help but wonder, is it possible to have a similar experience, if not the same, at your own home with your own hot tub?

Salt Water hot tubs are possible with a simple salt purification cell. Your saltwater generator can not just give you the benefits of soft, salty seawater but also keep the water clean, so you do not need to walk a tightrope with pool chemicals trying to balance the pH.

In this article, you will learn more about saltwater hot tubs, including everything you need to know before you decide to build or get one. What you will discover includes things that can get in the way of building a functional saltwater hot tub, why you need a saltwater generator in the first place, and whether it costs too much to make it worth your while.

Why Can’t I Just Add Salt to My Hot Tub?

The reason you even have to wonder whether saltwater hot tubs are possible is that they aren’t easy to build with your traditional tubs. You cannot simply dump a bucket of table salt in tub water and expect to have a saltwater hot tub because:

a) you will need to drain the water at some point, and

b) you will need to add more salt than is worth it.

The actual utility of a saltwater hot tub is not that it contains salty water; it is that it contains fresh saltwater. And for there to be fresh saltwater, there needs to be a constant generation (and supply) of saltwater via a saltwater generator. This is addressed later when we discuss why a saltwater generator is required in the first place.

Among other factors that can get in the way of creating a saltwater hot tub are the multiple logistical issues you might face. These range from modification limitations implemented by your homeowner’s association, landlord, or city council, depending on where you live. Therefore, it is essential to do your research and see whether saltwater hot tubs are banned or restricted in any capacity.

This is very unlikely but still worth checking because the risk of unknowingly doing something illegal is not worth taking. The next hurdle to keep in mind is that it will cost a pretty penny when you are starting with the building process. However, it becomes cheaper in the long run (more on this in the cost-specific section.

The final hurdle that you might expect when building a saltwater hot tub is that you might have specific allergies to saltwater. If you’re fine swimming in the sea, you will be fine in a saltwater hot tub. Still, the tub itself might be allergic to salt. Yes, corrosion of your hot tub material is something to consider. Generally speaking, a molded acrylic tub goes well with a saltwater generator.

Saltwater impacts differently on a case-to-case basis. That’s why there’s no general good or bad verdict regarding creating a saltwater hot tub. But when you set out to build one, you have to keep in mind that if one of your family members cannot hang out in seawater, They probably will not have a lot of fun in the saltwater hot tub.

The same goes for erosion and corrosion of the material. Salt is corrosive to certain materials only if exposed to in large enough quantities. This ties to why you need a saltwater generator in the first place.

What Do You Need to Build a Saltwater Hot Tub?

You need a saltwater generator because it will produce fresh saltwater and generate a stream of Chlorine, which comes from the reaction of Sodium Chloride (salt) and H2O (water). This constant mixing of salt and water produces a small, steady stream of Chlorine that purifies water in the right quantity as is needed to fill a hot tub and is simultaneously not too strong or concentrated to produce the unfortunately familiar pungent chlorine smell.

In fact, one of the best uses of a saltwater generator in one’s hot tub is as a cleaner. You don’t need to specifically measure pool chemicals and constantly shock the water because your saltwater generator has your back. But does this having your back come at a cost? Yes, initially, you will have to invest in not only a saltwater generator but the right coating or material for your hot tub, so it doesn’t corrode with excessive exposure to saltwater. 

However, if you look at the hundreds of dollars that you have to spend every year on pool chemicals and compare that to the amount of salt that is needed for a saltwater generator, you realize that you will be making your money back in about 2.5 years of saltwater hot tub usage. In other words, if you’re moving within two years, using a saltwater generator as a purifier isn’t worth the money. In every other case, it is.

Saltwater vs. Chlorinated Water for Hot Tubs

On the subject of purifiers, Salt Water vs. Chlorine is a debate that has been going on long enough in the aqua leisure community. Even though using Chlorine is a straightforward way of having stale water to be microbe-free and practically fresh for swimming. However, Chlorine is a chemical that requires delicate hands.

If you put too much Chlorine in water, it feels like swimming in a chemical soup, and your eyes may even water, but if you put too little, you might end up with water that stagnates, albeit gradually. A saltwater generator has the water flowing through it while it is constantly salting the water.

And that process in itself generates Chlorine which is for the most part enough to get rid of any impurities in a small enough pool of water, which a hot tub is. It costs less upfront to get Chlorine for your hot tub, but it is a lower-cost solution to get a saltwater generator because the saltwater cell will last you a few years before it needs replacement.

Are Saltwater Hot Tubs Expensive?

In the long run, you will save more money with a saltwater hot tub. The only exception to this is if your hot tub is made with material that reacts adversely to excessive exposure to salt. In that case, getting a saltwater generator is not the solution. 

You need to replace your hot tub, and that might be a higher-cost solution. If you compare that with simply chlorinating your existing hot tub, getting a new one and then adding a saltwater generator is quite an expensive way to save money on pool chemicals; you might not be able to make your money back for at least five years.

However, most people don’t turn their hot tubs to saltwater because they want to save on pool chemicals. They want the many benefits of saltwater hot tubs, including skin health improvement and the perk of having access to seawater. If you’re actually looking for those benefits, then there is no replacement for a saltwater generator because Chlorine will not get you anything close.

With the advantages briefly discussed, we have to look at the key drawbacks you need to keep in mind. Everything has some advantages and certain disadvantages, and it is impossible to have zero drawbacks.

The first drawback is the initial cost. You will need a minimum of $700 for a small hot tub, with the average entry price for a saltwater system being around $1,400. This, you will make back eventually with the reduced use of pool chemicals, water replacement, and reduced circulation requirement.

The second key disadvantage to consider is the corrosion of the hot tub itself. If you’ve not built your hot tub, then you can completely forget this disadvantage and simply invest in a molded acrylic hot tub. That way, you will not have to worry about corrosion.

If you already have a hot tub, though, you have to look at the material and research whether saltwater will corrode it. If it will, you must figure out how long it will take, so you can still offset this by simply researching which coatings you can use to avoid the constant exposure of saltwater to the hot tub frame.

Finally, there is the inconvenience of saltwater cell replacement. It takes a long time before the saltwater cell needs to be replaced. Only if you are willing to analyze the costs across a decade, you have to consider that the cell will need to be replaced at least twice in that period. Depending on your use, you can burn through more than four cells. Again, that is not as much of a disadvantage as the constant use of chlorinating chemicals, but it is also not a positive or even a neutral factor.

Final Thoughts

A saltwater hot tub is possible and is a low-cost solution across a long enough period, but it has some upfront monetary requirements that might cause some hesitation. Such a hot tub is ideal if you truly want seawater to be accessible in the comfort of your own home and want the many benefits associated with saltwater. However, if your current hot tub is made of material that might corrode with excessive exposure to salt, you might need to think twice before getting yourself a saltwater hot tub.

Jed Arnold

Jed spent every year from the ages of 15 - 22 as a Lifeguard (Red Cross) and ages of 17 - 22 as a Certified Pool Operator (CPO). Between working for over a dozen facilities and owning a pool, he carries over a decade of pool experience.

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