Saltwater vs. Chlorine Pools (Understand The Difference)

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Years ago, the only choices for a swimming pool were either a chlorine pool or no pool at all. Poorly maintained chlorine pools burned our eyes and noses, urban legends about green hair abounded, and we swam anyway.

Today, chlorine pools have advanced, but we also have the option of saltwater pools. And contrary to what some might think, that’s not just a pool with seawater in it. Seawater and saltwater are not the same things.

When comparing saltwater vs. chlorine pools, both pool systems keep the water clean and clear if proper maintenance happens regularly, and either one can provide you and your family with years of use. Whatever you decide on will come down to what you feel will work best for your situation.

Chlorine Water Pool

We put chlorine in our pools for sanitation and disinfection purposes. It’s an elemental gas that, when combined with sodium, creates salt, so it’s a substance most of us encounter every day, even if we never set foot near a pool.

Keeping chlorine in swimming pool water significantly lowers the risk of waterborne diseases being transmitted to and between swimmers. However, most people have been in or near a pool with too much chlorine in the water, which can irritate eyes, mouths, and noses. Higher amounts can cause skin irritation, as well.

However, chlorine is a valuable tool when it comes to maintaining pool water. As long as ratios remain at acceptable levels – usually two to four parts chlorine per million parts water – germs and bacteria won’t flourish.

Note, though, that chlorinated pool water does not kill algae. A high level of chlorine will kill organisms like algae, and this will be necessary if you find any organic growth in your pool water. But everyday chlorine levels, in conjunction with clean filters and functioning pool equipment, will keep any new algae from forming.

Saltwater Pools

While the word makes you think of the ocean, a saltwater pool is simply chlorinated with a different method. A few sentences ago, we mentioned that chlorine is one of the chemicals in salt. 

The way a saltwater pool works is that salt (regular old table salt, NaCl) goes into the water, then that water undergoes electrolysis, which is a fancy word for “having electricity sent through it.” The electrolysis process causes the chemical bonds to break, so the sodium separates from the chlorine, and the chlorine goes into the pool water. Every saltwater pool has a salt generator in which this process occurs. Once the ambient air temperature drops below 60 degrees Fahrenheit, this chemical process ceases to work.

The chlorine resulting from this process is not as harsh on the pool’s equipment or the swimmers themselves because it is less concentrated. Often, chlorine pools get their chlorine from concentrated tablets or powders that contain other chemicals, including several kinds of hypochlorites.

The chlorine in a saltwater pool is just chlorine. Without the other chemicals, the water of a saltwater pool is much gentler on swimmers’ skin. What’s more, since no hypochlorites exist in the water, you don’t have to keep such a close eye on the pool’s chemistry, adding this and that to balance out the pH and chemical levels.

Choosing Your Pool

With these options before you, you’ll consider the merits of each and how each fits into your lifestyle. Both kinds of pools require maintenance, so while people are often fond of saying saltwater pools are better because they require no upkeep, those people are wrong.

Chlorine Water Pools

Aside from the occasional skin and eye irritations chlorine pools can cause, other issues may loom larger. The biggest con surrounding your chlorine water pool sits squarely on the chlorine itself. 

Technically, chlorine is poisonous. World War I saw its use as a deadly weapon. Before you panic, lots of stuff you have in your house right now can kill you if misused, so don’t think you’re in danger. However, the danger exists, as you must store the chemicals in or near your home. If a kid or an animal got into the stuff, bad things would ensue. And also, accidents happen.

On the other hand, many people have owned pools for years and never had issues with the chemicals. Like anything, proper care and handling help ensure everyone’s safety. The biggest plus to the chlorine pool must lie in the costs associated with it.

The upfront costs are lower, and the ongoing costs of running the pumps and other machinery are lower than with saltwater pools. 

Saltwater Pools

For all the buzz around it, the fact remains that saltwater has its drawbacks. While the water will be softer and gentler than its chlorine pool counterpart, the salt used in the sanitization process can corrode and otherwise damage your equipment, decking, and even outdoor furniture.

Saltwater pools require less maintenance than chlorine pools, but when something goes wrong with your chlorine pool, you can do some DIY work. However, saltwater pool repairs have to be done by a professional. You might be a good tinkerer, but you’re not a saltwater pool technician.

The biggest issue with saltwater pools is the costs associated with them. The electricity required can cost nearly $50 per month, and that’s in addition to your regular electric bill. And initial installation costs are higher, as well. A saltwater pool can run you up to $40,000, so be prepared for that if you’re looking into one of these.

Why Chlorine Matters

Chlorine is what keeps us from getting sick from the pool. Remember that your swimming pool is essentially a closed system, so contaminants won’t flow out of their own accord if they get in there. Flowing water can take contaminated materials away with the river current, but our pools need assistance.

Chlorine, as mentioned above, is our sanitation tool in this case. Both chlorine and saltwater pools are kept clean with chlorine. The difference is where that chlorine comes from. Either way, without it, swimmers would be at risk for E. coli and cryptosporidium infections, among others, and those nasty pathogens can both pose significant health risks.

What Chlorine Doesn’t Do

The age-old question: did that guy pee in the pool? About ten years ago, one study revealed that 20 percent of Americans admitted to peeing in the pool. Imagine how many of the other 80 percent were lying. That’s a lot of urine. Add to that the fact that your skin currently houses about 1.5 trillion bacteria right this second, and when you jump in the pool, they all go with you.

If ten people are in a swimming pool, then, two of them are peeing in it, and along with that urine, up to 15 trillion different bacteria are swimming around looking for something to do.

Now, before you vow never to swim again in the face of those disturbing facts, all that stuff is what chlorine is for– keeping those bacteria at bay and disinfecting the water. What it can’t do is work perpetually.

We maintain pools (chlorine and saltwater) to ensure chlorination levels are high enough to do the job. However, every time chlorine has to seek out and destroy potential pathogens, whether from skin-borne bacteria, urine, or even fecal matter, its effectiveness decreases. Unless replenished, the chlorine will eventually stop sanitizing.

For this reason, the Centers for Disease Control recommends not peeing in the pool and that you should shower before you get in the water. Some things you think you don’t have to say, and then you find a study on the Internet that tells you, you were wrong.

One Last Maintenance Tidbit

Anyone who has maintained a chlorine pool has likely had to deal with shocking the pool. This process involves over-chlorinating the water in an attempt to kill any and everything in it (incidentally, you can shock with chemicals other than chlorine). A chlorine pool should be shocked once every one to two weeks to maintain all the chemical balance and sanitary conditions.

Contrary to popular belief, you must also shock a saltwater pool. When you think about it, this makes sense: saltwater pools, as we have learned, use chlorine to kill bacteria just like a chlorine pool does, so it would make sense that shocking was necessary. The good thing is that saltwater pools need it much less often – as sporadically as twice per year.

The Last Word

Both saltwater and chlorine pools are available in in-ground and above-ground pools. Homeowners can install either system with fancy decking around it or rocks and garden elements. Both kinds of pools rely on chlorine to keep the water clean and safe for swimmers.

Which one is right for you will come down to personal preferences. Do you want to do less maintenance and don’t mind spending a little more money on utility bills? Saltwater may be your jam. 

Is initial cost a potential issue? Chlorine water will fit that bill a little better. If chemicals on your property pose a problem, then chlorine pools with their accompanying buckets of chlorine in the shed may not be for you.

Spend some time researching your options, and also consider what you and your family want. If everyone likes the smell of chlorine, maybe your kids already settled the issue. When it comes to deciding between saltwater vs. chlorine pools, either option is a solid choice and will serve your family well for many years.

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