Swimming Pool Guides & Reviews by Certified Pool & Spa Operator®
Salt Water Hot Tub Conversion
Here’s Everything You Need To Know
Sodium chloride is the basis of salt. There are a lot of myths about saltwater hot tubs. Some people believe that putting pink Himalayan salts in the hot tub water will eliminate toxins from anyone who goes in it. Other people simply want to avoid putting chemicals in their hot tub water, so they use salts as an alternative. After all, using salts in a hot tub requires you to do a lot less maintenance work.
As far as toxin extraction goes, there is no proof that saltwater hot tubs can do this. However, the salts that go into hot tub water are more affordable than purchasing chlorine and spa sanitizer. You also won’t need to do much maintenance, either. Best of all, soaking in hot salt water does feel quite soothing.
The purpose of putting salt in hot tub water is to keep the water clean without using bromine, chlorine, or other chemical-based sanitizers. A saltwater chlorinator is used to turn salt into chlorine, which then cleans the water. Therefore, you won’t actually be relaxing in hot salt water once you try it out.
Once the ordinary water in your hot tub is turned into saltwater, the salt cannot be tasted. This surprises a lot of people when they experience it.
35,000 ppm (parts per million) is the salinity of seawater. Saltwater hot tubs are supposed to have anywhere from 2,000 to 3,000 ppm for their salinity level. Any salinity level past 3,550 ppm means that humans can no longer taste anything.
All you need to remember is to balance your hot tub water with just the right salt amount. Besides, you shouldn’t be tasting the water in your hot tub anyway.
Salt to Chlorine Conversion
You need a saltwater chlorinator, which is the same thing as a bromine generator or chlorine generator. Inside of the chlorinator, there is a chlorinator cell which consists of electrodes and titanium plates. You’re supposed to place the chlorinator into the saltwater of the hot tub. The chlorinator cell in the device will produce a very small amount of electricity.
Don’t worry because it isn’t enough electricity to cause people any harm. But it is enough electricity to convert the salt solution of the water into chlorine, which is a process known as electrolysis. During this process, chlorine is extracted from the sodium element of the salt.
Technically, you can use table salt in your hot tub, and it should work just the same. But it is recommended that you purchase the special canisters of hot tub salt that are sold in stores. The label on the product will read “Pool Salt” or something like that. Even though it is the same chemical as table salt, the difference is in how it’s ground. Hot tub salt is ground more coarsely to accommodate the chlorinator device. If you purchase the salt in bulk amounts, you can save plenty of money.
Advantages of a Salt Water Hot Tub
Choosing to use salt for your hot tub instead of traditional sanitizers has a lot of advantages. There is no magic cleansing that takes place, but it makes the hot tub experience a lot more relaxing and soothing.
Here are the advantages of a saltwater hot tub:
Gentler on the Skin
Chlorine sanitizing products contain chloramines. That is why chemical-based chlorine causes people to have trouble breathing and to feel like their eyes are burning. Fortunately, you won’t have this experience in a saltwater hot tub. The chlorinator only produces tiny bits of chlorine for the water. Not only does this balance the sanitizing effect, but it reduces the chloramines considerably. Saltwater is also much softer and gentler on the skin, eyes, and hair. You can’t go wrong here.
Saltwater hot tubs produce their own sanitizer a little bit each day. Because of this, you won’t need to do much water balancing or adjusting.
It is cheaper to purchase salt bags than it is to purchase liquid chlorine jugs. You can also handle salt bags much more easily. Once you give your hot tub water its first salt dosage, the salinity will remain steady as long as rainwater does not dilute it. For this reason, you can save money by not having to purchase salt regularly. If you were using chlorine, you’d have to purchase it all the time to keep up with the salinity.
However, salt water should still be tested regularly with pH test strips. You’ll want to make sure there is a balance of pH and alkalinity. In addition, you must conduct salinity tests with saltwater test strips.
Common Myths About Salt Water Hot Tubs
There are a lot of myths about saltwater hot tubs which exist. Let’s debunk these myths now.
No Maintenance is Needed
Regardless of which sanitizing method you use in your hot tub, maintenance will always be needed to some extent. There is no magic hot tub solution where you can just leave it alone, and it takes care of itself. Every 1 to 3 years, you must replace the chlorinator cells. In the meantime, the cells must be regularly soaked and cleaned in muriatic acid. Double-check with the manufacturer to make sure this is how you’re supposed to clean them.
No Chemicals in the Tub
Now, it is true that saltwater hot tubs don’t require you to purchase gallons of sanitizing chemicals. But this doesn’t mean that saltwater hot tubs don’t have chemicals in them. Since the salt is converted to chlorine, this becomes the chemical in the water. From there, you must balance the water chemistry by adding pH decreasing solutions and pH increasing solutions as needed.
Even though the salinity level is low, the saltwater of the hot tub may cause the metal components to corrode. It all depends on which heating element exists in the hot tub because not all of them support salt in the water. The best heating element to have is a titanium-coated element.
You can prevent corrosion by keeping the salinity level low and regularly clean the metal components which are exposed to the water.
Choose a Salt Water Chlorinator
There are different kinds of saltwater chlorinators on the market. The choice you must make is between an in-line chlorinator and a drop-in chlorinator. Electrolysis is used in both types of chlorinators to convert salt to chlorine. But there are some differences worth mentioning.
A drop-in chlorinator is the easiest and simplest method for converting salt to chlorine in your hot tub water. No special modifications to your tub are necessary for the installation. It should only take you a few minutes to set up everything.
The chlorinator cell does have a thin cord attached to it which hangs down from the side. This is not a huge deal, but it can be annoying.
To avoid the chlorinator line issue of the drop-in chlorinator, choose the in-line chlorinator instead. This particular chlorinator is integrated into the plumbing of the hot tub so that no line is hanging down from the side of it. The chlorinator actually merges with the circulation system of your tub.
Of course, you’re going to need a licensed plumber to perform this installation. Read the manufacturer’s warranty of your hot tub because in-line chlorinators may void the warranty.
The Conversion Process
Converting salt to chlorine is really easy. The hardest part is the preparation that goes into the conversion. But once you get through that, the rest is simple.
Here we will discuss how a drop-in chlorinator is installed. For anyone with an in-line chlorinator, either hire a plumbing professional or follow the manufacturer’s instructions.
1 – Drain the Water and Clean the Tub
The only way to switch between sanitizers is to remove all the water which has the original sanitizer in it. You’ll want the biofilm to be cleared out beforehand, so the line flush should be used first. Then drain the water with a sump pump or hose. Once the water is gone, use a smooth scrub sponge to clean the shell of the tub with diluted vinegar or a hot tub cleaning solution. Rinse the shell thoroughly.
Also, check the filter and wash it out too. If the filter is in bad shape, then replace it.
2 – Refill
You need to refill your hot tub with filtered water. Simply connect a hose filter to any standard garden hose and let it run water inside your tub.
3 – Conduct a Salinity Test / Add Salt
Conduct a salinity test on the fresh tap water because there may be some salt already in it. That way, you don’t end up adding more salt on top of the salt that’s already in the water. The instructions of the product will tell you what your salinity level should be at.
4 – Water Chemistry Test
You need to test the levels of calcium hardness, pH, and alkalinity of the water by using standard hot tub test strips. Refer to the chlorinator manual to see which levels these elements should be at.
5 – Mount the Control Panel
Your chlorinator kit should come with its own control panel as well as the necessary hardware needed to mount it properly. The control panel goes on one side of your tub. The power supply cable must be able to reach the ground-fault circuit interrupter outlet.
6 – Connect the Cables
The chlorinator cell cord and power supply cable must be connected to the tub. Don’t connect the power cord yet, though.
7 – Insert the Chlorinator in the Water
The power supply cable gets draped over the side of the tub. Insert the chlorinator into the deepest area of the water. Make sure it is as low as it can go because it’ll allow the sanitizer to spread more evenly in the water.
8 – Plug in the Power Cord
The power supply cord gets plugged into the GFCI outlet.
9 – Turn on the Chlorinator
You can now turn on your chlorinator. The manufacturer’s instructions will teach you how to program the chlorinator settings.
That’s it! Enjoy the tub!
Don’t Use Alternative Salts
You might think that table salt is like any other salt, and basically, it is. But you don’t want to risk adding other contaminants to your hot tub water. A lot of table salt, Epsom salt, and rock salt carry heavy metals or other impurities. Once these elements get into your hot tub, the water chemistry gets messed up. They could even cause damage to your hot tub and void any warranty that you may have.
Therefore, only use the hot tub salt that is sold in stores.
If you’ve never soaked in a saltwater hot tub before, your first time will feel incredible. The water will feel so soft on your hair and skin. Not only that, but you won’t need to add sanitizer as often as you did before. Overall, you’ll be spending very little money on hot tub supplies.
Why not give saltwater a try? If you do not like the outcome for whatever reason, you can simply switch back to chlorine. Most people do love the outcome after converting to saltwater, and we know you will too.