The Honest Truth About Salt Water Hot Tubs
Hey, everyone, and welcome to hot tubs 101 by Swim University, where we help you keep your hot tub clean and clear all year. My name is Matt, the founder of swimuniversity.com. And on this episode, we're talking about the honest truth about saltwater hot tubs. Let's jump in. Real quick.
Matt Giovanisci:If you want more help taking care of your hot tub, be sure to grab our free hot tub cheat sheet at swimu.com/spa sheet. So if you're looking to use fewer chemicals and have a gentler soaking experience, switching to a saltwater hot tub might be a good idea. And you can convert almost any existing hot tub with a saltwater chlorine generator. But before buying a saltwater system or before investing in a hot tub with a saltwater system, it's important to know the difference between that and a traditional hot tub, plus know if it's safe to use in your existing hot tub. So we'll bust several myths about saltwater that every hot tub owner needs to know.
Matt Giovanisci:A warning about saltwater hot tubs. So if you research, you'll be confused about the safety of saltwater hot tubs. And here's the truth. Saltwater hot tubs are perfectly safe to use, But stories are going around that salt water can be corrosive, and we've seen this happen. But that can also happen in a regular chlorine or bromine hot tub too.
Matt Giovanisci:So before you can convert your saltwater hot tub, check with the manufacturer of your hot tub to make sure this won't void your warranty if you still have one. And make sure that you follow, anything that we talk about for all of the proper techniques. You can go to our website swimuniversity.com. So what's the difference between a saltwater hot tub and a traditional hot tub? Well, a saltwater hot tub sanitizes your water by using the salt that's added directly to your water.
Matt Giovanisci:That salt in the water passes through what's called a saltwater chlorinator or a chlorine generator that converts that salt to chlorine or what's commonly referred to as hypochlorous acid. That's right. A saltwater hot tub still contains chlorine and salt. But instead of buying and storing and adding harsh chemicals to your water like chlorine, you're just adding salt, which can also be harsh, but we'll talk about that later. Now the salt that we're talking about is actually table salt.
Matt Giovanisci:It's the salt that you eat. And the companies that make that salt, Morton is one of them, they also make salt for hot tubs and they also make salt for pools. So after installing a saltwater system, it's likely you'll even be able to taste the salt. It's unlikely. Sorry.
Matt Giovanisci:It's not it's it's very, very low. So seawater, as an example, right, the ocean has a salinity of about 35,000 parts per million. That's a lot. The recommended salinity level for a saltwater hot tub is only between 20,031,000 parts per per million. So that's way, way less than the ocean.
Matt Giovanisci:And, obviously, if you're if you've ever swam in the ocean, you know it tastes incredibly salty. And if you've ever had pasta, that's kind of the water saltiness that you want when you boil your pasta. That's coming from an Italian. But 2 to 3000, it's not that much. Alright?
Matt Giovanisci:So as long as you add the appropriate amount of salt to your hot tub and you keep your water balanced, you won't be able to taste the salt. It'll be relatively undetectable. So for a saltwater hot tub, you'll need about 2 and a 1 2 and 1 thirds cup of salt per 100 gallons of fresh water. That's about 11 cups of salt for a large 500 gallon hot tub. Now that may even sound like a lot now, but trust me, it's not.
Matt Giovanisci:So how does a hot tub so how does wait. Well, how does hot tub salt how does the salt in the hot tub become chlorine? A saltwater sanitizing system contains a chlorinator cell composed of titanium plates and electrodes. So when properly, placed into salty water, the chlorinator cell uses a safe amount of electricity to zap or transform the salt into hypochlorous acid, which basically when you add chlorine to your water, it also turns into hypochlorous acid, and that's via a process called electrolysis. Right?
Matt Giovanisci:And that's as simple as it gets. So for this generator to work, you need to add either pool salt or hot tub salt to your to your water. I would not go ahead and add just any table salt to your to your hot tub. A lot of those salts contain things that, you know, anti caking agents and iodine that you really don't need in a hot tub. Right?
Matt Giovanisci:So, you definitely need that. And if you see it labeled as pool salt, right, so you may not see hot tub salt, but you might see pool salt, that's perfectly fine to use in your hot tub. This salt is chemically the same thing as table salt, but it's actually a coarser grind to work better in a chlorine or bromine generator. So only add pool grade or spa grade salt to your water. And if you want bromine in your water, you'll have to, you'll wanna add sodium bromine salts.
Matt Giovanisci:Right? So instead of, you know, converting it to chlorine, you need to find sodium bromide salts if you want it to convert to bromine. Alright? So real quick, what are the benefits of a saltwater hot tub? Well, 1, you get consistent chlorine levels.
Matt Giovanisci:Since saltwater systems continue continuously monitor your chlorine levels, they'll only generate as much natural chlorine as your water needs. Right? And this helps prevent extreme fluctuations and helps eliminate that nasty chlorine smell in your water, which is nice. Number 2, it's gentler soaked gentler, sorry, gentler soaking. Chloramines, the chlorine byproduct that causes the burning eyes and breathing difficulty, are reduced in a saltwater hot tub.
Matt Giovanisci:Because the chlorinator is continuously creating a small amount of chlorine, the sanitizer level remains more stable and keeps chloramines at bay. Also, salt water is softer water than traditionally chlorinated water, so it's easier on your skin, hair, and eyes. And if you use bromine, all those benefits are even increased. Right? So if you use the bromine salts, then that's gonna be even better for you.
Matt Giovanisci:Number 3 is you spend less time on maintenance. Salt water spas have a steady concentration of sanitizer being added all the time as we talked about. So the overall hot tub water chemistry may need adjusting, and you won't have to constantly buy and handle chlorine or bromine, but you still need to test and balance your pH and your alkalinity. That's still required. Number 4, it's reduced cost.
Matt Giovanisci:Now bags of salt are less expensive than chlorine or bromine, plus they're easier to handle. And after the initial dose of salt, your hot tub's salinity will stay relatively steady unless it's diluted with rain or you've added fresh water. This means that you don't have to buy salt as often as you would with chlorine or bromine. You still, however, need to test your water on a regular basis to make sure it's balanced pH and alkalinity. In addition to using standard test strips, you'll also wanna test for, pH alkalinity, and you'll need to test for salinity every month manually with saltwater test strips or a saltwater digital a digital saltwater reader.
Matt Giovanisci:They make these for, saltwater fish tanks, you can buy a digital reader for your hot tub if you want. Alright? Now, that said, reduce cost over time. Reduce cost, it's not it's gonna cost money to install the actual chlorine system. And I would imagine, you know, and I don't know this off the top of my head, but a saltwater hot tub that you buy from a manufacturer might be more than just not having one installed at all.
Matt Giovanisci:And I assume that that's true. Right? Okay. So let me debunk a few myths. Right?
Matt Giovanisci:So we just talked about the pros, but let's talk about the myths. Right? And these are kinda cons as well. So number 1, it requires no maintenance. You might hear that a lot.
Matt Giovanisci:All hot tubs require maintenance no matter what you use to sanitize them. No system is truly set it and forget it. So forget it. Chlorinator cells must be replaced every 1 to 3 years. So you still have to maintenance the actual chlorinator as well.
Matt Giovanisci:Until then, they need to be clean regularly. Typically, cells are cleaned by soaking them in ureic acid, but always defer to the manufacturer's recommended maintenance for your specific model. Number 2, people think that saltwater hot tubs are chemical free. While you don't need to buy or add chlorine or bromine to a saltwater hot tub, the end result is still water that contains chlorine or bromine in the form of hypochlorous acid. You also still need to add chemicals like non chlorine shock and you need balancing chemicals such as pH increaser, decreaser, alkalinity increaser, and you wanna keep the water chemistry balanced so that the salt water and the chlorine that it creates works.
Matt Giovanisci:Number 3, people think it's corrosion free, and you might hear that from a lot of the sales pitches for for saltwater hot tubs. And despite the low salinity in the water, because we talked about, you know, the ocean being 35,000 parts per million, right, which can be corrosive, but in a hot tub, it's 2 to 3000, so so a lot less. So despite that, saltwater hot tubs can still cause corrosion of metal components. For example, your hot tub's heating element may not be suited to salt and could corrode quickly if it's not titanium coated. So wiping down any exposed metals frequently and making sure your water isn't over salted can help prevent this corrosion.
Matt Giovanisci:So this is why it's important that if you are that if you're interested in converting your hot tub to a saltwater hot tub, that you wanna check with your manufacturer to make sure that it is ready to accept all of that salt. And if it can't, then I wouldn't do it. Or if you buy a hot tub, obviously, that has a salt water system in it, you wanna ask the manufacturer that, yes, does this have, like, a titanium coated, heating element, for example? I I would hope yes. So what are the different types of salt systems out there?
Matt Giovanisci:Right? So, again, any hot tub can be converted by using a saltwater chlorine generator. You can just buy this. They sell them on Amazon. Okay?
Matt Giovanisci:It's a drop they're called dropping chlorinators, so you can drop it in. You can add your salt. It's a little intrusive, I will say, and you have to, like, bolt the the device to the outside of the hot tub so you can control the salinity level or, sorry, control the chlorine level. And again, when I say that, make sure that you check with the manufacturer. So that's one.
Matt Giovanisci:And you can buy that. It's super simple and it's easy to install. It's not doesn't you don't have to take apart the whole hot tub. It's actually all on the outside of the hot tub. Right?
Matt Giovanisci:And you can go to our website, swimuniversity.com/saltdashwaterdashhottub if you wanna check out, the different systems that we recommend. The other one is the inline chlorinators, which don't hang over the side of your hot tub, which are not external. They're actually all built in. Right? And you can get this.
Matt Giovanisci:It's a little bit harder and it requires somebody to come and install it. So if you're not experienced, I would definitely hire a pro to do this for you. Right? And obviously, you can buy a hot tub with 1 already installed. Alright?
Matt Giovanisci:So let me talk about some frequently asked questions. We we we talked about how much salt do I need to add to a saltwater hot tub. We said about 11 cups for a 500 gallon hot tub, which is a very large hot tub and not a lot of cups of salt, honestly. Right now, there are a couple of, manufacturers that are selling saltwater hot tubs. Again, not every single manufacturer make you know, has a saltwater hot tub option.
Matt Giovanisci:But the 2 that come to mind are Caldera and hot spring. Those are those are the 2. Alright? And can you use any salt in the hot tub? No.
Matt Giovanisci:You don't wanna go into your pantry and grab any salt that you have, kosher, diamond kosher. You don't wanna grab, you know, gray salt, Celtic salt. You don't wanna grab Morton, all of this stuff. Some all all salts contain some type of additive. Right?
Matt Giovanisci:Now you can what about, like, Malden flaky sea salt? No. Don't do that. Just to be safe, go buy pool grade or hot tub grade salt. That's what you wanna do.
Matt Giovanisci:So that's the truth about saltwater hot tubs. And remember, if you need more help with hot tub maintenance, grab our free hot tub cheat sheet at swimu.com/spa sheet. If you found this episode helpful, subscribe for more hot tub maintenance tips on your favorite podcasting app. And when you do, please leave us a review. That would mean the world.
Matt Giovanisci:And it would and your support by leaving a review will help more hot tub owners like you find this show. That's it. Thanks again, and happy soaking.
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