ozone

[MarkTilley]

I'm really surprised there isn't any discussion on this site about ozone generators.

Does anybody have any experience/knowledge to share about ozone systems (any kind)?

Can anybody comment on the Del TrioPure product that combines ozone and a SWG in one unit?

Our condo is considering replacing the chlorine system in our 36,000 gal. indoor pool with an alternative sanitizer. The pool is not heavily used on weekdays (we have 450 suites) but often has 10-15 swimmers on the weekends. There's also a 1,000 gal. spa.

Any recommendations appreciated.

[DavidD]

Mark,
There has been discusion regarding ozone generators in the past. See this on the forums sister site
http://www.poolsolutions.com/tips/tip48.html
Ben, the forum moderator makes some excellent points here.
If you are going to spend the money, I would opt for the SWG without the ozone...

[grochmal]

I'm surprised as well about the lack of info here about ozone.
The page that David refers to has some very old information on it (old in terms of ozone technology).
Ozone is very popular in Europe and I use it on my salt water reef aquarium.
Corona discharge is pretty much the de facto standard technology in use now which allows for a large amount of ozone to be generated.
Much more than UV.

The last note on David's page refers to what I believe is the common practice use of ozone - ozone generator with combined use of low levels of chlorine for residual sanitation.

I am very excited about the prospects of using lower levels of chlorine and wished more people using ozone technology knew about this website and posted their experiences.

[waterbear]

If you use ozone in Reef aqariums(I've been keeping reefs for about 30 years now) you know that:
1. ozone is poisonous....more so than chlorine
2. ozone has no residual effect in the water and is actually only sanitizing the water in the reaction chamber
3. ozone in reef aquairims is usually introduced in the protein skimmer and there is no equivalent of that piece of equipment in a pool or spa.
4. ozone has little effect on algae
In sanitizing a swimming pool:
1. Choose the safest sanitizer both in terms of sanitizing ability and ease of use...I vote for chlorine
2. residual sanitizier is NECESSARY to keep the water safe.
3. the simpler the equipment the easier it is to take care of
4. algae can be one of the biggest problems with swimming pool maintenance and chlorine is usually the first cure that you should try.

I say keep the ozone in your reef tank (I don't even use it in mine anymore and can keep even higher ORP readings as a result) and get a SWG for the pool. This will eliminate much of the problems with combined chlorine and the problems associated with it. There is even a unit with a built in ORP controller available now from Autopilot that will automate the chlorine production even more (Cue Poolsean to take over )

[PoolDoc]

I'm really surprised there isn't any discussion on this site about ozone generators.

<snip>

Our condo is considering replacing the chlorine system in our 36,000 gal. indoor pool with an alternative sanitizer. The pool is not heavily used on weekdays (we have 450 suites) but often has 10-15 swimmers on the weekends. There's also a 1,000 gal. spa.

Sometimes, the absence of discussion is an example of following Grandma's rule, "If you can't say something nice, try not to say anything at all."

But, sometimes, it's necessary to get real. It always amazes me how people can be accustomed to hearing, on the one hand, that there are smog problems today, because the "ozone levels are high", and then, on the other hand, get all excited about 'natural' ozone in pools.

The 'real' fact about ozone is that, for residential outdoor pools, the promotion of ozone is mostly hype and hot air . . . and the pursuit of more $$$ for a couple of manufacturers.

It *is* possible to use ozone to produce truly outstanding water quality. But the technology to do it with (corona discharge generators) is neither new nor misunderstood. What it is, is complex, expensive, and dangerous. It's used very, very effectively in a number of indoor commercial pools in Europe, mostly in Germany. But, the system used is very expensive, and requires continuous on-site expert supervision.

The reasons why ozone is so difficult and expensive are twofold, and very simple.

First, ozone and chlorine mutually destroy each other, when effective levels of both are present.

Second, ozone is more toxic than chlorine, and less soluble.

Effective levels of ozone can NOT be allowed to reach the pool, because unlike chlorine, the ozone tends NOT to stay in the water. Consequently, effective ozonation systems require a detention chamber, and then a stripping chamber, before the water can be safely returned to the pool. Effective levels of ozone, if not stripped, can kill people, and have done so. To quote an article from the Journal of American Toxicology, abstracted by PubMed, "Ozone is one of the most toxic and ubiquitous air pollutants". Woe unto your pool's swimmers, if you allow ozone to remain in the water returning to the pool!.

Likewise, effective levels of ozone cannot be allowed to reach the point of chlorination, lest both the ozone and the chlorine be destroyed.

So, how have US ozone system manufacturers solved this problem? Easy! They just build systems that put ineffective levels of ozone in the pool water!

The typical UV based systems used in the US are *safe* only because they are *ineffective*! They can "sell" only because Barnum's maxim about buyers is still true.

There are also some corona discharge systems sold hat are "intrinsically safe", a fact which is sometimes advertised as a 'feature'. But, again, an "intrinsically safe" ozone system is also "intrinsically ineffective" one!

To promote ozone as an "alternative sanitizer", as some manufacturers do, is simply dishonest!

Again, the reason is simple.

Pool sanitizers, in commercial pools, MUST be where the people are, in order to stop person-to-water-to-person transmission of disease pathogens. This is not a theoretical problem. The CDC has documented, summer after summer, public outbreaks following transmission via the "from their rear, to the pool water, and thence to your mouth" method . . . almost always courtesy of inadequate filtration and chlorination.

For ozone to be a pool sanitizer . . . it has to BE IN THE POOL! But, for safety reasons, ozone can NEVER be in the pool, only in the piping system. Therefore, something else must be. In the very effective German systems, the something else is always chlorine!

There's nothing new about any of this information. It was well understood in the potable water treatment industry, here in the US, and in both the pool and potable water industries, in Germany, LONG before I wrote my PoolSolutions' page on the topic. There have been incremental improvements in systems, but nothing that changes the basic facts of ozone chemistry.

I'm surprised as well about the lack of info here about ozone.

. . .

The page that David refers to has some very old information on it (old in terms of ozone technology).

. . .


I am very excited about the prospects of using lower levels of chlorine and wished more people using ozone technology knew about this website and posted their experiences.

The reason for the lack of information about ozone systems is simple: the systems that work, are NOT appropriate for pools built for under $100,000, or pools which lack an onsite system engineer. If you are planning such a $100,000+ pool, and will have an intelligent on-site facility manager who can be trained to operate such a system safely and effectively, be my guest. You'll be able to get outstanding water quality that way.

But that's puts you outside the group I'm trying to serve here. My goal is to help people here, who are not in the $100,000+ pool market, achieve water quality that's nearly as good as what can be produced with such an ozone system.

In addition, on outdoor pools, exposed to the far more benign oxidizing effects of solar UV, the disproportion between the small benefits of effective ozone systems, and their large cost is huge.

Ozone does have benefits for indoor pool treatment, which is far more difficult than outdoor pool treatment. Successful indoor pool treatment, especially on heavily loaded commercial pools is difficult, and the difficulty is made worse by the burden of inaccurate or inapplicable information supplied by the pool industry. I have very deliberately kept indoor pool treatment issues segregated here. It's a small market, and a hard problem. There are solutions, but they are too site-specific, and too complex for a discussion directed at consumers, such as the one here at PoolForum.com .

I recognize the value of ozone for aquarists; in fact, I've several times finagled my way into see the systems used at the Tennessee Aquarium. (These systems do, by the way, generate high levels of ozone, which is stripped after passage through the detention chamber.) Ozone has value in aquatic treatment, precisely because its problems (insolubility) become a benefit: unlike chlorine, ozone is easy to get out of water!. Chlorine and its byproducts are simply intolerable in an aquatic environment . . . precisely because chlorine is so very effective at keeping water 'dead'. Ozone is less effective, but far easier to remove, and does not produce the byproduct stream that halogens do.

Live warm water is just 'naturally' pond like, but that's NOT what pool owners want. They want clear blue warm water which is, almost by definition, 'dead' water.

Aquarists, on the other hand, want water that is 'alive', but not 'too alive'. As you know, 'grochmal', maintaining a reef enviroment is labor and technology intensive. Multiple levels of filtration, protein stripping, ammonia control, oxidation by UV and ozonation, maintenance of saline balance, operation of biologically active filters, and more, are all part of the daily requirements for the serious aquarist. It is very fortunate, that virtually none of this is necessary for pool owners.

After all, for *most* pool owners, the pleasure does not come from the challenge of pool care; it comes from actually *using* the pool themselves. Chlorine makes this easy. Ozone just makes it more complicated and expensive.

So, the reason for the "lack of info here about ozone" is very simple. For owners of residential outdoor pools, ozone can only get in the way of achieving the goals I have for pool owners: that their pools become easier, cheaper, better and more fun!

I'm tired; it's late; and I've a chunk of my evening flogging a long dead horse! Hopefully, this will be the only time I have to do so this season!

Sincerely,

Ben Powell
"PoolDoc"

[waterbear]

Well said! Perhaps you might want to consider putting this info into a FAQ and 'sticking' it in the forum. It is info anyone putting in a pool or spa should have. Ozone seems to be getting a hard sell these days. I had 2 different builders include ozone systems in their quotes when I was first shopping for my pool/spa a few years back! If I had not had personal experience in using ozone in fish tanks I might have made a mistake and put one in becasue they DO look good on paper!

[PoolDoc]

Well said! Perhaps you might want to consider putting this info into a FAQ and 'sticking' it in the forum. It is info anyone putting in a pool or spa should have.

Yeah, I plan to do so. But I was tired last night, and anyhow, these things read differently to me after a day or so. I want to edit it, before I stick it!

Ben