Regular Salt Vs. Pool Salt

For those diving into the responsibilities of owning a swimming pool for the first time, upkeep can seem daunting. There's cleaning, chlorinating and filtering. Perhaps you're hearing about the growing trend in having a saltwater pool, but is it worth the bother? What's the difference between table salt and pool salt?

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Chlorine is generally necessary to keep pool water clean and safe, but chlorine can be murder on the skin and hair for some people. If you've ever spent an hour or two in the pool and emerged with that burning-eye feeling once you're back on your feet, you know exactly what the chlorine problem is. It's almost like a chemical burn.

By using a saltwater chlorine generator (also called a pool salt cell) for a cleaning system in your pool, the salt tempers the chemical feel. It's a salinity akin to that of human tears, so it doesn't burn, it doesn't leave your hair dried out and it doesn't irritate skin.

Why does salt work so well for pools? The secret is in its elemental name, NaCl – sodium chloride. When pool salt enters the water, it dissolves and breaks into sodium and chlorine ions, and the chlorine ions then react with the water, turning into hypochlorous acid. The hypochlorous acid performs much the same as chlorine tablets do but in a kinder, gentler way with all of the sanitizing and none of the burn.

So, what's the difference between table salt and pool salt, then? In ideal circumstances, pool salt is even more pure. It can't be iodized like table salt often is. It needs to be 99.8 percent pure food-quality salt with no anti-clumping agents. Using the right kind of salt is critical to the health and well-being of your saltwater pool cell.

Evaporated and mined salt are preferred. There is an evaporated salt called solar salt, made through natural evaporation by the sun, but this also is more impure due to the briny carcasses of sea creatures that died as the water vanished. Mechanically evaporated salt is more pure but also has more minerals remaining in it. Mined salt is extracted from the earth and is the most pure option.

The use of salt chlorination technology has skyrocketed in recent years as costs have come down some, and homeowners realize the initial expense is offset by years of simpler, cheaper maintenance. At first, getting the chlorinator can be pricey and so can the starting salting costs. However, then comes the true reward of salting your pool: low upkeep with only adding salt once a year or when you put fresh water into the mix.

The pool cell's basic job is to throw some electrolysis into action, which molecularly separates the sodium and chlorine. There are titanium plates in the cell that make this happen, and the result is chlorine that becomes hypochlorous acid and battles bacteria microorganisms while keeping your pool healthy for the year ahead.

Over a third of American home pools had switched to salt-based systems by July 2018. The saltwater chlorinator for a 25,000-gallon pool can run around $800, give or take. A 40-pound bag of pool-grade salt – coarser and noniodized – is about $30. Then, for about $10-15 a year in salt, the pool is maintained without the addition of chemical chlorine-based tablets, and it's this ease of maintenance that is so attractive.

The better hair, softer skin and lack of burning eyes certainly don't hurt saltwater pool popularity either.