Pool Ozonators, by Mike Fournier, Tulsa, Sonrise Pools
Ozone oxidizes impurities that pass the inlet. These impurities include lotions, oils, pee, ammonia, and some biologicals. Shortly after passing the inlet, any unused ozone will break down. It has a 1/2-life of a little over 20 seconds. It's this short life that prevents a residual from protecting the main body(s) of water.
Free chlorine oxidizes almost as well as ozone and it kills more things like algae and lasts in the water much longer before gassing off or doing work such as sanitizing. The levels in the pool can easily and inexpensively be tested.
If an organism forms slime on the wall of your pool, ozone has no way of attacking it. When a child (or adult) pees in the pool, it can take over 4 turns of the pool volume before it's all neutralized if there wasn't any chlorine.
The same holds true for sweat (you do perspire in a pool), tanning lotions, skin oils, fecal (human, bird, and so on) etc., that all need to be oxidized and rendered harmless. Chlorine kills biologicals such as algae and bacteria quickly because it's in the pool already and is certified as a primary sanitizer by the DEP. Ozone is only a supplemental for a pool and when used with non-chlorine shock, may be primary in a portable tub.
If you test for total and free chlorine and they are not within .5 ppm of each other, you know something is going on in the pool. The chlorine is fighting something. Having an ozone system may help fight some things for a short period. Proper levels of chlorine kill all unwanted impurities.
Since chlorine does it all, there is little use for adding additional items like ozone generators, ionizers, mineralizers, etc... to a residential pool. They need servicing and that is an unneeded cost for residential pools and often a high margin expensive addition to the builder.
Some commercial pools that have very high bather loads or very fast flows or very large surface areas (water parks) benefit the most by having an ozone system.
If you have a party and 20 people are in the pool playing, the residual will be used. Most people learn to turn the chlorine level up before and then shock it after to ensure no water borne illnesses infect the guests.
If you depended on ozone, it might take four turns of the water to get it all. That could take a while. The water borne illness, in that time is multiplying, often as fast as 20 minutes. A turn of the pool volume may take 8-12 hours. That is a lot of multiplying time available. Chlorine kills over 99% of the water born bugs in seconds of contact.
Some germs are resistant but will die eventually. Fortunately, they are slow to reproduce Cryptosporidium is one such bug and is very rarely seen in residential pools. Ozone takes it out on contact. Chlorine may take an hour, more or less depending on the free chlorine level, but gets it too.
If you feel you want to add an ozone system for your own peace of mind, great, but don't think that it will reduce the needed levels of chlorine in the pool. Someone, maybe you or a family member will still get a rash, the hersheys, or your pool will appear hazy, go green, etc...
Want to talk about it some more? Would you like a quote for any of these areas? If yes, send me an e-mail to: Sonrise.Construction2000@Gmail.com, and be sure to mention this blog. I will be back in touch with you shortly. Thanks.