What Is The Best Pool Water System?
It is common for pool owners to search for the best pool water system once they learn that there really are many different ways to approach caring for and maintaining their water. You might expect that it is a simple matter of following some technical protocol but as it turns out there is a lot of gray area around exactly which technical protocol will result in the optimum outcome. I don't mean to sound elusive to the uninitiated, but this is the reality of managing pool and spa water. I am your pool guy and I build you a pool or renovate yours back to health so you ask my opinion as to what the best way to care for the water is. I tell you to use chlorine and balance your total alkalinity and pH, along with a few other chemical details that you largely ignore. You are already picturing copper ions dancing in your mind.
How could there not be a better solution than chlorine. The answer is so obvious to you that it never even occurred to you that chlorine might actually be the best option you have. There must be an alternative because you have read about ozone injection systems, germicidal UV lights, advanced oxidation process, copper ionizers, antimicrobial silver, active enzyme treatments, biofilm removers, hydrodynamic cavitation, salt water systems, Polyhexamethylenebiguanide - one of these HAS to be better than chlorine, right? Wrong. First, one of those things on the list does not belong, and that is salt water because salt water is just a regular chlorine pool so that is not an alternative to chlorine, just an alternative to where you get your chlorine from. Hopefully this is not new news to you, and if it is then I insist that you take a moment to read my article get informed about salt water pools.
Getting back to the rest of the list, I will ask you a very simple question. Can you name for me any commercial swimming pool that you can go to near your house that does not use chlorine, but instead uses any one of the peripheral devices or chemical processes as an alternative to chlorine? You might have a pool near you that is open to the public that utilizes one or more of these systems in addition to chlorine, but can you name a single one that uses only the methods listed above with no chlorine at all? For 99.9% of you reading this the answer will be no. Do you think that every commercial pool in America uses chlorine because "big chlorine" bureaucrats want to keep you down somehow? No, chlorine is in your drinking water, the water you cook and eat with, the water you bathe in and the water you bathe your children in. Trying to avoid chlorine by using an unsafe alternative in your pool while continuing to drink it in your water and cook and clean with it daily...this just makes no sense. Here are the four reasons we use chlorine in pools, as well as in all water supply systems:
Chlorine is a sanitizer
Chlorine is an oxidizer
Chlorine is an algicide
Chlorine can hold a residual value in the water
This is the ultimate list of criteria which must be satisfied in order for your water to be safe. Each and every item, device and chemical process above fails to meet at least one of these four critical elements. You can pick any one from that list and it will be missing one of these four things. Ozone for example is an oxidizer, and works great with a few limitations. It can not build or hold a residual value in the water which means it does not function or provide benefit until the water has been pulled in through the filtration system and had the opportunity to pass through the ozone injection point...or UV light, or any other system other than chlorine.
Benefits Of Chlorine In Pools
I understand completely the mindset of the pool owner who wants to find an alternative to chlorine and I am at risk of losing you as a reader right now because I am not giving you the information that you want to hear. I deal with that a lot as a pool professional. I prefer however to make informed readers and listeners and I encourage you to continue reading even though I have just crapped all over every one of the chlorine alternatives you have been researching. But all is not lost. I do have some good news for you and I think this is a great compromise that we can meet in the middle with.
You want an alternative to chlorine because who wants more chemicals in their lives, right? Usually it comes down to the kids as well because they are smaller and in the water so much. They practically drink a pitcher of pool water per day when they are out there splashing around all day. This is the reason that you don't want chlorine in the water, but strangely also the main reason that I do want you to have chlorine. The ability to hold a residual value in the water is really hard for alternatives to chlorine. This is why you should keep using chlorine, but the good news is that chlorine is actually pretty awesome, and can work with almost any other system or chemical process out there. This is without a doubt the secret to the cleanest, healthiest and safest water in a swimming pool. Utilizing more than one system and specifically selecting your water management system to have synergy.
An example of synergy in a pool water maintenance system would be first of all to use chlorine as your baseline for safety. It works, we can test it to verify, and we can manage the levels of chlorine readily in the water by maintaining pH, total alkalinity and cyanuric acid within the correct ranges. Now, add in a piece of peripheral equipment or a chemical from the original list above and you can benefit from both. One tried and true combo is chlorine along with a germicidal UV light. If you had to find a weak link for chlorine there might be two things you could point out:
Chloramine buildup - You need to measure free chlorine in your pool but also the total chlorine so that you can deduce the combined chlorine level in the water. Combined chlorine is the chlorine in your water that has found some bacteria or organic debris to attach to, or combine with. This combined chlorine no longer shows up on your free chlorine test, but it does in the total chlorine test. Combined chlorine should be zero, but as it grows and approaches 1 part per million the water will begin to smell like chlorine. When you complain of a pool that smells like chlorine you are noticing one of the weak aspects of chlorine as a stand alone solution, in that you need to do something called breakpoint chlorination, which some pool owners mistake as "shocking" the pool. In essence you need to raise your chlorine levels very high for a while to burn off the combined chlorine such that your free chlorine reading and total chlorine reading become the same. Clear as mud right? Chlorine gets used up, and needs a huge blast of more chlorine to get rid of that used up stuff which kind of smells bad and makes your eyes itchy.
Cryptosporidium - Exactly as in the example above, with cryptosporidium chlorine lacks the ability to kill this important parasite. Or more accurately it lacks the ability to kill cryptosporidium within an appropriate timescale based on the levels of free chlorine normally maintained in pool water. It is not just enough that your sanitizer works eventually, it must do so within an aggressively fast timeline. This is why something like silver is not suitable as a stand alone solution in your pool water despite having some known bactericide properties. It is because the timescale to kill things in the water at the levels maintained in pools is insufficient, by quite a long shot actually. At 1ppm free chlorine almost everything dangerous in pool water is dead within 60 seconds or less. Silver is measured in hours or days, which is not even in the same world as 60 seconds or less. However cryptosporidium has an outer shell often described like a basketball that low levels of chlorine would take hours or days to kill. Even weeks. Which is why superchlorination, or shocking, should be done to the pool periodically. This is expressly because chlorine lacks the ability to kill this one problematic parasite.
Germicidal UV lights are a fantastic compliment to chlorine based systems because UV works great at deactivating cryptosporidium as well as oxidizing combined chlorine which can drastically reduce on the total chlorine that needs to end up in your pool. If your free chlorine number and total chlorine number always remain the same, which means that chloramines are not building up in the water because the UV light is constantly reducing their number, then you no longer need to do the breakpoint chlorination process. Similarly with cryptosporidium there should no longer be a concern for this if you brush your pool, turnover your water at least three times per day through the filter, and maintain your free chlorine level above one part per million always (and CYA in the 30 to 50 range only). This in my opinion represents the best water system and pool water maintenance process available to the average pool owner. Yes there are other options, and other combinations of systems, but this one works great, is easy, does not cost a lot, is pretty easy to install, and universally should make an improvement to every pool it is installed on.
For UV lights available in the USA take a look at this article that includes Pool UV light reviews
For UV lights available in Canada you can shop directly from PSC for UV lights for pools
There might be other systems which rival this, or arguably are better such as AOP systems in particular, and it is only purchase price combined with the relative new-ness of these systems that makes me lean towards this recommendation for chlorine along with a UV light. If you have deeper pockets and you like to be at the front of technology waves then you might be more interested in looking at pairing chlorine along with an AOP system. Advanced oxidation process along with chlorine in low levels probably represents the future of "the best pool water management system" where I consider the chlorine and UV light the best system of today that is affordable and accessible to every pool owner regardless of how big or small your pool is.
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