Salt or AOP UV/Ozone? Or Salt AND AOP UV/Ozone?

October 19, 2021

Here is a question we read all over social media. It gets asked of our Tech Support team and Sales team. Customers want to know: Should I add a salt chlorine generator to my pool? Or should I add AOP? (they like to call it a UV/Ozone system, too)

This article is going to answer that question, once and for all. What pools should use salt – what pools should use AOP? But we do have a confession. The answer is actually a bit of a cheat. What if it’s not a question of either/or?

Believe it or not, the right thing to do is to use both an advanced sanitizer and a chlorine generator. Let’s take it one step at a time. First, why would you choose either of these technologies in the first place?

What are the benefits of AOP?

CMP Next Gen AOP™ from the makers of DEL Ozone®

Advanced Oxidation Process (“AOP”) is a powerful sanitizer. In fact, the process of using UV and Ozone together creates hydroxyl radicals and this the most powerful oxidizer available for a residential pool.

What does that mean? Here are the benefits. AOP . . .

Kills what makes you sick. Viruses and bacteria, all dead. In fact, AOP can destroy microbes that chlorine will take hours or days to kill on its own.
You can reduce chemical use. This applies whether using a chlorine feeder or chlorine generator. While you still need 1-3 parts per million (ppm) of chlorine, it will take FAR less to maintain that residual. So you add less to the pool, you handle fewer tabs, you can run the generator less, etc. It saves you money and chemical exposure.
Your water can be crystal clear. You may think you have clear pool water but if you haven’t seen AOP water, you haven’t seen clear. With AOP water you can see details 10ft deep in the water. It is crazy clear.
You will not have any chlorine irritation (chloramines). The vast majority of chlorine complaints are actually due to chlorine bound up with other things in the water, creating chloramines. Chloramines smell, they are irritating and burn your eyes. But AOP destroys these, so no chloramine – no problem.

What are the benefits of a salt chlorine generator?

In the pool chlorine floats around in the water, ready to destroy all kinds of things, algae, bacteria and other contaminants. It’s not a super-fast process but it is happening constantly.

With a salt system, chlorine is produced on-site through the chemical process called electrolysis. Salt (sodium chloride) through the electrical reaction becomes chlorine. This process creates “free chlorine”—the most effective type of chlorine in the pool. Once the process is over, the chlorine converts back to salt so it’s a continuous process.

This has a ton of benefits:

Yep, make your own chlorine. No more buying buckets of tabs. No more storage in the garage. No more handling and smelling strong chlorine. You just make it yourself.
It’s a better version of chlorine than you can buy! Every form of chlorine has to be packaged in some way to make it sellable. It’s just part of the process. But that does mean there are additives, binders, and different concentrations. In this case the system makes pure chlorine and injects it into the pool – that’s it.
Making your own chlorine is also better for the environment! Chlorine production requires a whole factory process to make the tablet or liquid. It has to be shipped around the country (there are only a few locations that manufacture most of the pool chlorine we use). And of course you are exposed to it in your home. One hundred percent of this is eliminated by a chlorine generator.

A Powerclean® Salt cell inside its clear housing on a pool pad.

Pools using traditional chlorine systems typically experience sharp peaks and valleys of chlorine levels depending on bather load and other factors. You end up having to shock the pool when levels get out of control. Another benefit to salt is that the chlorine generated creates a consistent “baseline” in the pool, which helps you avoid that need to shock.

Powerclean® Salt chlorinators are a very convenient way to sanitize a swimming pool using chlorine, without needing to keep buckets of tabs and pool shock lying around. You can convert just about any existing pool to salt without a ton of complication, and installing them on new pools is a breeze!

But what if you use both?

Now we get to the “meat” of the whole argument. Both of these systems sound great, just check out the list above. But did you notice, their benefits are not the same. Maybe this seems like a difficult choice. But actually it presents a fantastic opportunity. These two systems actually mesh perfectly, complementing each other with their different benefits.

How Can AOP Make Salt Better?

You can get the most out of a chlorine system—like a chlorine generator— by adding a powerful advanced sanitizer like DEL AOP®. AOP makes salt better by requiring less chlorine and reducing overall chlorine usage. Essentially, you get more bang for your buck from the chlorine generator.

You can run the system less ( we have customers who literally run it at half the recommended level). This can extend the life of the salt cell. It also means you have to clean the salt cell way less often.

Above we already hinted at a couple other complementary benefits. AOP destroys dangerous microbes that chlorine may take a very long time to kill. It prevents swimmers from getting sick.

We also talked about AOP destroying chloramines. These also exist with a chlorine generator, it’s just nature. But with AOP this will not be a problem. The water will feel better and smell fresh.

How does Salt Make AOP Better?

By now you may be asking yourself, “Self: if AOP is so great why do I even need to add a salt system?” It’s all about the residual. While they do actively sanitize, supplemental sanitizers like AOP do not work on their own.

AOP reacts with the water when it passes through the system. This is really powerful, but it happens in one spot. There is no “AOP” in the pool water you are swimming in. Anything introduced to the pool needs to circulate through the AOP to be treated. You still need to keep a residual sanitizer level in the pool. That’s where Powerclean® Salt comes into play.

Powerclean® Salt – The Friendly Backyard Chlorinator

Powerclean Salt produces a residual in the form of free chlorine. A residual sanitizer keeps working in the open water at all times, even when the pump is off. This helps keep swimmers safe the entire time they are in the pool. Unlike a filter or AOP system that the water must pass through to be cleaned, a residual sanitizer is right there in the water and all around the swimmers.

Complementing Systems for Complete Benefits

Consider hybrid cars—automobiles that use a combination of electricity and gasoline. There’s the electric component that is doing most of the work (AKA the AOP unit), and gasoline is your backup (AKA the chlorine generator).

Again, you could drive with gasoline only, but that’s old tech. Why not make life easier and switch to new equipment that has so many benefits and is more efficient? That way you can move on to the next job quicker. You get the best of both worlds with the synergy of salt and AOP.

The industry has been working with clean water technology for quite some time, so none of this is new. Chlorine, salt, ozone, and UV have all been around for decades. It’s only natural that as we continue to work with the tech and obtain valuable feedback from pool professionals like you, we improve on the equipment used to keep our pool water safe.

Salt + AOP: A True Testimonial

One of the first test subjects for our Next Gen AOP, was Vic Walker a CMP employee. On his new pool he installed AOP and also a Powerclean Salt system. He had very high hopes, but even those were exceeded. Here was his experience:

“We have a teenage daughter and she brings her friends over to enjoy the pool occasionally. The other day we had nine girls in the pool one day for several hours. The water was not cloudy at all after all that time. They were covered in makeup and lotions before they got in the pool, too. But, at the end of the day, I could still see the screws in the drain cover at the bottom of my pool.”

“Not only that, we experience it every day when we swim. Let’s face it, who is going to be more critical of the pool water than the family in the water every day. I keep my chlorine at a minimum of 3ppm, sometimes higher. My wife will swim and then lean down to smell the water. She never smells any chlorine.”

“And both of the ladies in my life (wife and daughter) have no complaints about how the water feels on their hair, skin, or swimsuits. The pool is always crystal clear and the whole family could not be happier.”

Next Generation DEL AOP® installed on a pool pad.

Finding the Right Solution

Sometimes a solution comes along that feels almost perfect. Chlorine tabs are old tech. Salt systems are new-ish tech and AOP is the new hotness. It used to be about either using what you grew up with or maybe installing the newest thing.

But the alternative is The Complete Modern Pool®. The modern pool is ready for anything swimmers and contaminants can throw at it. Plus it uses fewer chemicals and is better for the environment. It’s the whole package.

By combining the best of new pool technology, a pool can be clean, clear and safe all the time. And of course, we didn’t stop there. We also designed DEL AOP and Powerclean Salt products for durability, easy operation and simple service. Start here if you want to learn more about what these systems have to offer.