Jandy SWCG's "optimal" water conditions: why raise CYA?

[waterbear]

I just posted this in another thread about an hour ago. Please read.

I raised my CYA to 45 ppm

NOW raise it up to where it SHOULD be (around 80 ppm), drop you TA to 70 if it is higher than that, and start saving money on acid and maintenance and stop being a big tall dumb guy and become a big tall smart guy!

[waterbear]

So, Cya of 30 and FC-1.5, running a SWCG/DE Filter 12hours a day on 50% isn't necessary?
I should raise CYA to 60 and FC of 3 with less time on the cell?

I must say this is a great forum...

NO, you should raise it to 80 and maintain the FC at 4 ppm. The difference between 60 ppm and 80 ppm has been determined to be significant and directly translates into better pH stability in a salt pool.

[waterbear]

"You're starting to believe, but I don't think you're quite there yet."

You're right. The proof (for me) will be how this forum's methodology holds up in *my* pool, right? But everyone here has convinced me that I don't have to blindly and ignorantly follow a local pool store's advice on how to care for my pool (for which I heartily thank you!). Moreover, you've raised an interesting, viable alternative that I'm willing to try -- keep up my CYA level, keep up my FC level, watch over my CC level, and shock only when the pool needs to be shocked. Doesn't have to be once a week. Doesn't have to be once a month, even. Just when I need it.

You have just stumbled on to the secret on how commercial pools are maintained!

So, I'll give it a go. My "insurance policy" against algae, though, is that I'll still add a maintenance dose of polyquat each week. The relatively low cost of doing that gives me peace-of-mind. What I need to work out now is how much time the SWCG needs to operate to keep up the FC level. Over this week and next, I should be able to nail that answer down.

Adding borates to 50 ppm is a better insurance policy, only has to be done once and you don't need to worry about it until the level drops to 30 ppm (for most people this is once a year), and they also help keep the pH from rising as fast so your pH becomes even more stable.

[famousdavis]

Supermom said, "Just an FYI (and somebody may have already told you this earlier in this thread -- I didn't take the time to re-read it) -------- polyquat will cause your FC to plummet. Then you'll have to add more chlorine to pull it back up."

I had a dip in my FC after doing a maintenance dose of polyquat, but it didn't plummet:

FC on Tuesday morning (which followed a SWCG shock on Sunday-to-Monday): 7 PPM
FC this Wednesday morning (polyquat in the water 24 hrs): 5 PPM

And the drop may not be entirely the polyquat. I'm trying to figure out how long I need to run the SWCG, and I think it's set right now so I l lose a little FC each day (0.5 to 1 PPM).

Waterbear: I dumped 3.5lbs of stabilizer in the skimmer this evening after getting a 55 PPM reading from my CYA test. Great tip you gave on re-testing the CYA using the same water, btw. I tried three times just to make sure I got repeatable results (I did). I think my problem with my earlier CYA testing -- where I kept still seeing a little bit of the black dot, even after I added all 14ml into the tube -- was because I didn't wait long enough before pouring in the mixture. Taylor's instructions say wait at least 30 seconds, but waiting a couple of minutes is much better. Anyway, I'll take a reading tomorrow and see if my CYA level is up around 80 PPM. Then I'll continue leaving my SWCG settings alone (50% for 8 hours) and see what happens to my FC levels. Thanks so much for providing some clear advice on chemical levels!

[famousdavis]

*Apologies. Watermom + Super Moderator = Supermom.

[famousdavis]

So I tested my water today, 24hrs after adding more CYA in my pool. CYA is now 80. I tested my FC today, too. Instead of losing 0.5 or 1 PPM like I have been with my current settings (50% for 8hrs), my FC actually rose 0.5, to 5.0. And today was a full-sun kind of day, too!

I may tamp down my SWCG to 40% tomorrow and see what happens. I want to stay near the 4 PPM range.

I get my water tested by the two pool companies tomorrow, too. I can't wait to compare my results again with what their test results say! After tomorrow, I may just release the one company that uses test strips from doing my pool water analysis -- I think their test results are way screwy, especially with my TA and FC levels. Pinch-a-Penny's drop-based testing more closely aligns with my own testing, though last week they came up with a much lower FC level than what I came up with using the K-2006.

[famousdavis]

So I took two water sample from my pool this morning, gave one to The Pool Store (test strip testing) and one to Pinch-a-Penny (drop-based). Plus I did a few tests with my K-2006. Results:

FC
The Pool Store: 2.3
Pinch-a-Penny: 3.0
K-2006: 4.0

CC - everyone agrees, there is no CC

pH:
The Pool Store: 7.9
Pinch-a-Penny: 7.6
K-2006: 7.5 (yesterday's reading)

TA:
The Pool Store: 150
Pinch-a-Penny: 140
K-2006: 90

Ordinarly, The Pool Store has read way higher than Pinch-a-Penny, so I was surprised at today's high TA from Pinch-a-Penny. I was also surprised at their recommendation: that I add 1.3 gallons of muriatic acid into my pool! However, I watched closely the testing process at Pinch-a-Penny this morning. The gal had to run the test twice because the first time her TA reading was, I guess, astonishingly high. During the second test, the reagent she added that turned the water from green to pink resulted in only a slighly higher reading than the "Ideal" markings on her big test tube that measured the amount of reagent she was adding (Pinch-a-Penny says "Ideal" is between 80 and 120). Clearly, there was an imprecise testing process at work that led to the wide discrepancy between her two tests! And even though her second test showed high TA, I did notice that she tended to add a few more drops of reagent even after the water turned from green to pinkish-red. After her high reading, I went home and re-tested TA using my K-2006. I noticed that when I test, I do so MUCH more slowly and deliberately. And I stop immediately after the water turns from green to pink color (the 9th drop of reagent changes a blood red color to pink). Pinch-a-Penny uses Taylor reagents, too, but their setup is different where they measure reagent from a test tube that they're adding to the swirling water, whereas I am counting drops of reagent. I think the speed with which they perform their test compared to my own testing explains the differences in our results. I'm also confident that my reading is correct because I used their last week's TA reading (80) which also matched the K-2006 reading for last week to add just enough baking soda to get to about 90-100 PPM (this was before Waterbear's advice to keep the TA at the low end of "Ideal").

CH:
The Pool Store: 300
Pinch-a-Penny: 350
(I didn't test this since it's been stable since I got our pool)

CYA:
The Pool Store: 75
Pinch-a-Penny: 80
K-2006: 80

CONCLUSION: I think I can now test my own water using the K-2006 as well as the "pros" at Pinch-a-Penny, and I can do a decidedly better job of testing my own water than the test-strip folks at The Pool Store. So I'll "fire" The Pool Store and move to less frequent visits at Pinch-a-Penny, just to ensure I maintain the warranty requirements on my Diamond Brite finish. And I'll trust my own judgment -- and the judgment of this forum -- more than the advice I get from Pinch-a-Penny.

A BIG THANK YOU to this forum! I feel like a Pool School graduate today. :-)

[BigTallGuy]

NOW raise it up to where it SHOULD be (around 80 ppm), drop you TA to 70 if it is higher than that, and start saving money on acid and maintenance and stop being a big tall dumb guy and become a big tall smart guy!

I ordered my Taylor K2006 test kit via Ben's link and I am waiting for it to arrive so I can do proper testing. You may remember that I had an extremely bad experience with CYA a few years ago and I would like to know who sets the 80 PPM standard for SWCG Pools, and why.

My SWCG owner's manual says 50 PPM of CYA, and I believe I read one of ChemGeek's post that says the higher above 50 you get the CYA, the more it actually counter acts with chlorine. In addition, I still need to run my filter at least 4 hours a day for a good turn over.

SO HERE IS MY QUESTION TO ANY AND ALL POOL OWNERS WITH A SWCG THAT KEEP THEIR CYA AT 80 PPM AND THEIR CHLORINE AT 4.0 OR HIGHER, DO YOU EXPERIENCE OR GET COMPLAINTS ABOUT BURNING EYES? BE HONEST, BECAUSE THAT WAS MY EXPERIENCE.

[waterbear]

I ordered my Taylor K2006 test kit via Ben's link and I am waiting for it to arrive so I can do proper testing. You may remember that I had an extremely bad experience with CYA a few years ago and I would like to know who sets the 80 PPM standard for SWCG Pools, and why.
The manufactuers and for some of them it's as high as 100 ppm such as for the unit you have. Actually, a lot of it came from discussions on here and on TFP and chem geek is an integral parto of it. It came from the range that SWCG manufactuers recommended and it is the upper limit for most of them (Some units, set the upper limit at 100 and Penair sets it at 85. I don't know of any that set the upper limit at 50 ppm btw.) It was determined that SWCGs operated most efficiently at the upper limit of CYA and had the best pH stability.
My SWCG owner's manual says 50 PPM of CYA, and I believe I read one of ChemGeek's post that says the higher above 50 you get the CYA, the more it actually counter acts with chlorine. In addition, I still need to run my filter at least 4 hours a day for a good turn over.
No, I think you have that confused. There is evidence that above 60 ppm CYA has a direct UV blocking effect in water. Chem geek wrote quite a bit on that either here or at TFP, I can't remember which.
Also, if I remember correctly you have a compupool CPSC-24 which has a MINIMUM CYA level of 40-60 ppm and a MAXIMUM level of 100 ppm (as do many of the Australian units) so your CYA should be at 100 ppm and your FC at 5 ppm. When you posted about burning eyes your CYA was at 50 ppm and your FC at 5.
SO HERE IS MY QUESTION TO ANY AND ALL POOL OWNERS WITH A SWCG THAT KEEP THEIR CYA AT 80 PPM AND THEIR CHLORINE AT 4.0 OR HIGHER, DO YOU EXPERIENCE OR GET COMPLAINTS ABOUT BURNING EYES? BE HONEST, BECAUSE THAT WAS MY EXPERIENCE.

I have never known CYA to cause burning eyes (and my own has been at 80 ppm for several years now). pH problems can cause burning eyes. Chloramines can cause burning eyes (and with high CYA and bad pool management it is very possible to have persistent chloramines.)

YOUR CYA should be at 100 ppm. If you don't believe me look on your manual on the first page after the table of contents where it says at the bottom that CYA should be maintained at 40-100 ppm and that 40-60 ppm is the MINIMUM where it should be maintained. I have explained many times WHY higher CYA is beneficial in a salt pool (and for that matter it is often beneficial in a non salt pool, as Ben and the mods can tell you also.)

When you posted problems of eye irritation it is very possible that your FC was very high since you said it was 5+ and you did not have a test kit capable of testing high chlorine levels (or FC for taht matter so it is possible that you also had chloramines present and that would explain the eye irritation.)

Bottom line, it's your pool and you can do what you want but if you want ot minimize the problems associated with salt pools and save money then raising your CYA to 100 ppm is in your best interest.

I realize that you are very slow to take the advice here since you just now ordered a good test kit even though it's been recommended to you for quite some time. I understand that you have a problem with an overstabilized pool in the past (I suspect you were using trichlor at the time) but to try and correlate that experiece with managing a salt pool is comparing appels and oranges. High levels of CYA are not intrinsicially bad or evil but many seem to think so. In acutallity, CYA is the best thing that every happened to outdoor pools. Stabilized chlorine, on the other hand, can be problematic since it continaully causes CYA to rise to levels high enough to cause problems.

[famousdavis]

Just an epilogue to yesterday's "pro" water testing and my own K-2006 test results. Yesterday I tested my TA after The Pool Store said I had a TA of 150 and Pinch-a-Penny said my TA was 140 (and who also said I should dump a LOT of muriatic acid in to bring down the TA). My K-2006 said I had a TA of 90. My OTO test kit also had a TA test I could perform, and it said I had a TA of 90.

So today I took another water sample (without having done anything to my water since yesterday) to a different Pinch-a-Penny on the southside of my town. Guess what? According to them, my TA was *too low* (75) and I was supposed to add alkalinity increaser to my pool!

What a bunch of bologne!

In the cases of drop-based Pinch-a-Penny, I observe them *hurriedly* working through their various tests, and that leads, I believe, to a lot of imprecision when it comes to rinsing out their tubes and correctly measuring the amount of water they poor into their tubes and jars. For one Pinch-a-Penny to test my TA at almost one-half of what the other Pinch-a-Penny determined is just plain ludicrous.

How happy I am that I can do my own water testing, saving me from regular weekly trips to the pool stores! I'm going to save a TON of money doing my own testing and carefully adding *only what's needed* to my pool, rather than blindly following the "expert" advice of the pool stores!