Ultraviolet pool sanitizers

[bishop9000]

Hi, this is my first post. I was just wondering if anyone had any opinion or experience with ultraviolet pool systems. I have a 20,000 Gal. inground pool. Currently using a Compupool salt generator. Thanks for any help.

[chem geek]

UV is a supplemental system only and does not replace chlorine. It has some use in commercial/public pools where either UV or ozone is used to help kill the protozoan oocyst Cryptosporidium parvum which is very chlorine resistant, but that's not needed in a residential pool where you aren't swimming with strangers that have diarrhea and where one person could infect hundreds. UV is also useful in an indoor pool to help control chloramines since there is no UV from sunlight to do so.

However, in an outdoor residential pool, there isn't normally a need for either UV or ozone because the bather load is low in a residential pool so chlorine is able to do the job just fine by itself, especially with the UV in sunlight helping out.

[waterbear]

UV is not a primary sanitizer not is it residual. It is of some use in a commercial indoor pool to help break down some oxidation byproducts but is totally unnecesary in an outdoor pool that get even just a few hours of sunlight (UV).

Edit: I guess chem geek and I were posting at the same time.

[Foxeau]

It is claimed by some of the UV sanitizer manufacturers that using them, one can safely reduce chlorine levels in a residential pool to 0.5ppm

Here is one person's account of his setup of a system in his residential pool to do that:

http:/\/\mainframereview. com/\what-i-learned-about-pool-spa-ultraviolet-uv-filter-systems/\

Has anyone else here tried that?

[PoolDoc]

Jon/Jill;

It's not necessary to hit my finger with a hammer, to know it's a bad idea.

The site you linked -- and I broke the link -- is not a disinterested account first person account. "Mainframereview.com" is a affiliate marketing site, selling the stuff they fluff. To quote from the index page, "You can purchase some of the products you read about in our ONLINE STORE."

Plus, the article about UV is bogus. Just to take the easiest shot at it, the pipe picture they use, presumably to illustrate what happens without UV, is actually a steel water pipe, probably used for potable water. It has tubercular corrosion, mediated by bacteria growing in the tubercular cells.

The picture below, is a totally bogus picture, when used for that article. Steel pipes have not been used on pools for at least 45 years, plus that particular pipe is too small to have been used on pools at all. Instead, the writer just lifted a random photo found elsewhere, because it served his intention to deceive gullible readers.

In the picture, you can see it's just a 3/4" galvanized water pipe, probably used in household water:



Foxeau, please do NOT post any more links to bogus 'reviews' of UV systems for pools or potable water. If you want to post links to peer-reviewed scientific or engineering studies, that's fine. But post another link like that one, and you're gone.

You've asked your question; we've responded -- TWICE. Asking again is NOT going to make an outdoor pool at 0.5 ppm FC functional or practical.

If you want a different answer, go elsewhere. There are plenty of 'environmentalist' discussions where you can find someone to tell you that the absolutely best way to take care of your pool, is to use a solar-powered ozone-generating UV-irradiating "GREEN" system sold by some company, like "HippiesWhoNeverPassedHighSchoolChemistry, Inc", OR "AsianMarketingSharksRippingOffGullibleLaowai, LLC".

But, we're not going to do that here.

photos & article archived in Picasa album folder

[Foxeau]

Dear Ben,

Thank you for your reply with clarification. I was fooled by that article - it did not seem bogus to me when I first read it. On closer inspection, I see that you are correct and it is a product ad masquerading as an impartial review. I've been all over the internet researching and trying to learn as much as I can as fast as I can and that one tricked me. You see, we had a Chlormatic II SWCG that just kept on working year after year, while our local pool service came out once a week to do the other chemical adjustments to our in-ground, 10k gallon pool. He said our SWCG (which they installed some 7 or 8 years ago) was the only one they knew of that was still working. Then he stopped coming 1 per week, down to every other week, and as you'd likely predict, the pool got pretty messed up - very green water, then long-lasting bubbles and "Don't go swimming in it until tomorrow since I put in all the chemicals" etc etc. Then the SWCG failed and so the pool guy left us a gallon of 'chlorine' in a generic, unlableled white bottle to "Dump in the pool in 3 days."

So we've said enough of this and started researching, beginning with looking into getting a new SWCG, since Chlormatic was bought out and the parts are getting pretty hard to get, and more expensive than a new, different brand of SWCG. All this research led us to this forum and the BBB method, but also to all the many, many websites offering ionizers (Cu-AG etc) and UV sanitizers and ozonators. After some phone calls to some of these places, it is clear that they are indeed pretty bogus - one ionizer place said they wouldn't put a pdf of their manual online because "the competition would steal our ideas."

All of this has been very revealing indeed. I think our pool problems were just waiting to happen, since now I think that there is just no substitute for daily testing and daily adjustment. Doing this once per week, and for sure every other week, will just not ever work and will inevitably lead to problems. And at this point, since we're both going to learn how to do this ourselves, and do it daily, the benefits of a SWCG seem pretty minimal. Instead, we'll put our money into a shed near the pool with the chemicals and test kit we'll need, and maybe a pool vacuum to make it easier/faster to get out all the leaves that are going to fall into the pool in October. We haven't yet started researching pool vacuums, so we don't know how much better/faster they'll be than our long handled basket scoop-net - but since we are in our 60's, we'll probably need to go with solutions that are not too strenuous.

All the urgency to get this right as soon as possible is because we have grandkids coming over, other guests this weekend, and the pool guy still hasn't shown up and so we need to start taking care of our pool ourselves now!

Lastly, we keep trying to update our profile on this forum by clicking on "My Profile." But we always get the same error message:

"You are not logged in or you do not have permission to access this page. This could be due to one of several reasons:

You are not logged in. Fill in the form at the bottom of this page and try again.
You may not have sufficient privileges to access this page. Are you trying to edit someone else's post, access administrative features or some other privileged system?
If you are trying to post, the administrator may have disabled your account, or it may be awaiting activation."



I'd really like to update our signature, put in our location (Northern California) and so on - can you please look into this or send it on to the right administrator?

Thanks,

Jill and Jon

[Watermom]

You can update your signature. In the right-hand corner near we here you log in, click on 'settings.' From there you can click on 'edit profile.'

Hope this helps. Welcome to the Pool Forum, by the way!

[PoolDoc]

All the urgency to get this right as soon as possible is because we have grandkids coming over, other guests this weekend, and the pool guy still hasn't shown up and so we need to start taking care of our pool ourselves now!

Going to the immediate issue, urgent care for a 20K gallon pool:

1. Purchase a cheap local OTO / phenol red test kit (yellow / red drops) at Walmart

2. Purchase 16+ gallons of 8.25% household bleach and 4 boxes of 20 Mule Team borax at Walmart

3. Purchase 1 gallon of 31% muriatic acid at Home Depot, Lowes, etc.

4. Assuming your pool is algae free, add 2 gallons of bleach this evening.

5. Retest the following evening. If you have OTO DARK yellow, skip the dose; medium yellow => add 1 gallon; clear to light yellow => add 2 gallons.

6. Each evening before adding bleach, test the pH. If the pH is below 7.2, add one box of borax, slowly to the skimmer while the pump is running. If the pH is above 7.8, add 1/4 gallon (approx) of muriatic acid directly to the pool. READ the muriatic acid safe-handling page (linked in my signature block) BEFORE using the acid.

7. Continue in this fashion, till you have a K2006 test kit and results, and have ANOTHER maintenance plan ready to go.

8. Order the K2006 from Amazon; we've never seen them sold locally. Link in my signature block.

[Foxeau]

Thank you! Now we get to work...