Pool & Spa Professional is part of the Informa Markets Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Troubleshooting Saltwater Pools

Saltwater open-air pool
Adding more salt to a saltwater pool isn't the remedy. Find out from Biolab's Alicia Stephens some of the chemistry issues common to saltwater pools and ways to troubleshoot ideas to the problems.

At the 2021 PSP/Deck Expo, Alicia Stephens, Education and Training manager at Biolab, Inc., a KIK Custom Products Company, led a session titled “Saltwater Pool Troubleshooting: Beyond the Equipment.” 

This seminar focused on the chemistry issues common to saltwater pools and provided clear troubleshooting ideas to the problems. 

Saltwater pools are chlorine pools, Stephens noted.  

"Any product you can use in a chlorine pool you can use in a salt pool is that simple," she said. "They're compatible. 

"What salt does is it replaces the need to handle sticks and tabs and liquid chlorine and things like that," she continued. "In order to sanitize the pools, we automate that first step of sanitizing filling bacteria and keeping that pool clean and clear. 

"Hydrochloric acid is the molecule in the pool that does all the work for you," Stephens added. "Do you want to use salt or do you not want to use it? Please know that regardless of which way you go, the end result is going to be the same. You're going to create hypochlorous acid. When you create hypochlorous acid you're going to kill bacteria, sanitize the pool, etc. So what you're really managing with those is the byproducts and the after-effects that happen with whichever form of chlorine you happen to choose." 

Stephens broke down the basics of chlorine generation to attendees. 

"We have water obviously, right? You put in salt. You actually create chlorine gas initially," she said. "You create some hydrogen, you create some sodium hydroxide, right? And then the process goes on like pouring gas recombobulates the water and you create hypochlorous acid.  

"It's that simple, right? You take your shaker of salt. You shake it into the pool, you add a little bit of electricity. What comes out? Hypochlorous acid," Stephens continued. "But remember: I said no matter how you get the hydrochloric acid, what you're managing is the byproducts and the after-effects—and that's where we can get into trouble with saltwater pools." 

During the session, Stephens dispelled the myth that adding salt is "all you need." 

"Has somebody ever managed the salt pool appropriately or effectively by just putting in salt?" she asked. "It's not quite that simple, right? But what you can sell a homeowner on that. 'Just put salt in. That's all you need.'  

But Stephens looked at the truth behind that. 

"First of all, a salt cell generates unstabilized chlorine," she noted. "But you have to know that with a saltwater pool, it is creating unstabilized chlorine. So, with unstabilized chlorine, you are susceptible to the UV rays of the sun. You will lose that chlorine you're generating very quickly unless you add stabilizer.  

 "The process that the cell uses to convert salt into chlorine leads to higher pH. There's no way around that; it happens. You can treat for it you can mitigate it, but you can't stop it from happening," Stephens added. "The environment within the cell itself is very conducive to forming scale. It's just the way it works inside the cell. You've got electricity, you've got high pH. It's very conducive to forming scale.  

"Chlorine is effective at killing bacteria when you make it from salt, but you do still get the byproducts that you find with a traditional chlorine pool," she continued. "So you still get all the stuff that happens when you break down and kill bacteria when you break down the contaminants. So shocking a saltwater pool is still a really good part of the pool maintenance."   

However, as Stephens pointed out, adding more salt to the pool doesn't solve all your problems.  

"I have talked to 1,000 homeowners," she said. "You've got to look a little deeper beyond the high level of just what is your salt level in order to troubleshoot saltwater pools." 

What are some of the most common issues with saltwater pools? 

"First and foremost is pH balance," Stephens said. 

Next would be not holding chlorine. 

"There are about 100 different reasons why you can't hold chlorine in a saltwater pool, only one of which is that you don't have enough salt," Stephens said. "So let me just say that more salt does not always solve your problems. But you can break those hundreds of reasons down into basically two categories: You're either eating up the free chlorine so fast that you can't keep residual or you're not making the free chlorine in the first place. It's that simple." 

Third, is excessive combined chlorine "because a lot of people don't shock saltwater pools," she noted. 

The other issues include cloudy water, surface and scaling problems and algae. 

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.