Is stabilizer necessary?

[JimK]

I was reading this link ( http://www.truetex.com/poolcontrol.htm#cyanurics ), and the section titled "Eliminating Cyanurics" caught my attention. According to this article, stabilizer isn't needed and in fact makes it much more difficult to sanitize the pool and extremely difficult/impossible to kill algae without having to shock on a regular basis.

He states he does not use stabilizer and can sanitize/kill algae with far lower free chlorine levels (well less than 1ppm; I think he mentions .2ppm or so). It seems unstabilized chlorine is extremely effective even at low levels.

Has anyone tried this method? Can it be done when using a SWG (mine recommends CYA at 60-80, would a CYA level of 0 hurt it?)?

I understand CYA prevents UV from depleting the chlorine quickly, but also greatly reduces its effectiveness. Would a SWG be able to keep up with demand without using any CYA or prematurely depleting the cell?

Seems like this method could save quite a bit of $$. Any thoughts/experience with this are greatly appreciated.

[BigDave]

Yes, it is in an outdoor pool. Please read through this thread which contains a discussion of the need for stabilizer.

I've read the pool automation website and I think it's a pretty neat project but essentially misguided.

Feel free to post back here after looking over the thread above if you have any questions or if something is unclear, I didn't reread the entire thread today so...

[JimK]

Thanks for the link.

I read through that thread but was left even more confused. I really didn't see anything in that thread that discussed the need/benefits for using CYA and why it's better to use it than not. The focus of the thread seems to be on Kent Williams and the disagreement with his recommendations and how some here do not like him. But the link I posted was written by Richard Kinch. In the thread you mentioned Ben/PoolDoc says this:

"...Richard knows more about the chemical relationships among chlorinated cyanurates in pools than anyone I know . . "

Is he talking about the same Richard? If so, then I'm really confused as Richard seems to be advocating not using CYA.

As I'm certainly FAR from being and expert (just a pool owner who's trying to learn how properly to take care my pool without wasting a bunch of time and money on it) I would greatly appreciate some guidance and clarity.

Thanks.

PS - If it matters, I have an outdoor IG 20k gal. vinyl pool with an Aquarite SWG and Hayward DE6020 DE filter.

[BigDave]

Jim,
I'm sorry, I didn't choose the best example in the thread I referenced. My bad. There are better discussions here on Pool Forum.
The important thing to understand is: in a stabilized pool, more chlorine is available where it needs to be to destroy pathogens that enter the water.
Stabilizer binds a percentage (a large percentage but not all) of the Free Chlorine, this protects the chlorine from the sun but also prevents it from sanitizing the water. This applies only to the bound chlorine which is a portion of the Free chlorine. When the portion of the unbound chlorine is used up reducing some "dirt" that gets in the pool, the stabilizer releases bound chlorine to become unbound chlorine and maintain the portion of unbound chlorine to bound chlorine. This newly unbound chlorine is immediately available to attack more "dirt" in the place where the dirt is.
On the other hand, in a pool with no stabilizer, all the Free Chlorine is available to attack the "dirt" but when the supply of chlorine in the immediate vicintity of the "dirt" is exhausted, the remaining "dirt" won't be sanitized until circulation and dispersion bring more chlorine close enough to it.

[JimK]

Thanks Dave. That information is helpful. So bottom line, I should stick with the CYA levels recommended by the manufacturer of my SWG?

Some info for reference.....

One reason this topic caught my attention is my personal experience over the past several years dealing with algae in my pool (my pool was installed in the spring of 2004 and it's the only pool I've ever owned). It seems despite keeping CYA in the 60-80 range, FC 5-7, and PH 7.5-7.6, the liner would keep getting slick (start of an algae breakout?) and I would have to shock and brush the pool frequently. Based on a recommendation a few years ago, I started using borax (maintained at 40-50) and polyquat 60 (I add a maintenance dose of 8 oz per week). Since doing this in combination of shocking every couple of weeks, I no longer have an issue with a slick liner. However, I do still get some visible algae in grooves and crevices (such as where the liner meets the steps and behind the trim around the pool light; possibly due to poor circulation in those areas?) which I'll brush out before my regular shock treatment.

I'm tempted to discontinue the polyquat 60 to see what happens. That would save me a couple hundred dollars a season, but I'm hesitate to mess with what's currently working well for me. Except for the addition of polyquat 60 and Jack's Magic Purple Stuff (since using this I have no more staining issues which I'm told is a side effect of the SWG), I pretty much follow the BBB method.

BTW, except for a few spring openings when I was using a mesh cover over the winter (I use a solid cover now), my pool have never been green (during the season it's always clear).

[Watermom]

Yes, stick with the CYA levels recommended by your SWCG manufacturer. And, not the same Richard. "Our" Richard is "ChemGeek" who is a valuable member here on PF.

[JimK]

So not the same Richard, that makes much more sense.

While you were posting, I was editing my post. Any comments on the info I've added?

Thanks.

[Watermom]

Go ahead and try it without the Polyquat and just be diligent about keeping up with your chemistry. You can always go back to using it if you decide you need to. I never use any Polyquat, not even when closing my pool. I'm consistent about my chemistry and don't really need it. What I don't have to spend on that, I can use to buy something else like maybe dog food! My 3 golden retrievers go through LOTS of dog food!

[JimK]

Go ahead and try it without the Polyquat and just be diligent about keeping up with your chemistry. You can always go back to using it if you decide you need to. I never use any Polyquat, not even when closing my pool. I'm consistent about my chemistry and don't really need it. What I don't have to spend on that, I can use to buy something else like maybe dog food! My 3 golden retrievers go through LOTS of dog food!

Thanks for the response. When I'm feeling brave and ready to experiment (lol), I'll give it a shot.

[waterbear]

The article you reference is using ORP controllers to monitor the redox potential of the water (and not directly monitoring FC levels) and using a liquid chlorine injection system. First fact, CYA disrupts ORP controllers so systems that use then do not use CYA (or use very reduced levels). Second, his system has a pretty much constant chlorine 'drip" going into the pool. This is how many commercial systems are run out of necessity but it is not necessisarily the best way. I have also worked on a commercial install that used peristaltic dosing pumps for both liquid chlorine and acid for pH control but did not have any electronic control. The 2 pools and two spas at this installation were tested 3 times a day and the dosing pumps adjusted if needed. However, once they were set up they needed very little adjustment to keep everything where it was supposed to be.
The info he references in the article (including teh one from Kent Williams) are mostly from those with connections to ORP controller manufacturers so it is in their best interest to say that CYA is NOT beneficial because when you use ORP control it is a problem and makes the system malfunction.