Experiences of a newbie - Liquidator, borates, CYA testing

Chaddy

0
Aug 21, 2013
25
Austin, Texas
Hello all. I've just registered and this is my first post, but I have obtained a wealth of information from this site, so thank you all. Our pool was completed in December 2012. We started with trichlor pucks and by July the CYA was at 98, at least according to Leslie's, which is another issue I will try to get to later. So I started to search for information and found TFP. I immediately switched to liquid Cl and then found the Liquidator. I was able to connect the output from the Liquidator to the drain plug on the basket in front of the pump and the input to the Liquidator to the output hole from the puck feeder that I removed. I can post pictures if the setup is of interest. I also recommend wrapping the Liquidator in insulating wrap for high sun locations. White stuff (WS) appeared immediately at a pH of 7.6-7.8, CYA ~100(?), TA~100, CH ~250. So I kept the pH at 7.2 and TA~70 but the WS was still a problem. I had to take the flow meter out because it would clog almost immediately and I changed the small ball valve with a larger one to try to improve the flow. Every day I would have to turn the valve back and forth to try to break up the scale. I had to clean the parts in acid about once every two weeks. So I was a bit worried about constantly having to deal with this. But then I found the magic dust. Borates. 10 boxes of Borax and three gallons of acid for my 12,500 gallon pool. It took a bit more acid to bring the pH down into range. I am waiting on some LaMotte strips to test my borate level. The drop test seems to be impossible to find now, as the Canadian company can't ship to the US. Anyway, it has not been a week yet and the WS is gone. Just this evening I put the flow meter back on. From what I can tell so far the borates have significantly reduced my Cl usage. I will have to follow up on this, but I was using about 1/2 a gallon per day, and now it seems to be 1/4 gallon. Still probably too early to tell. My pool was always sparkling clear, so I have not noticed a significant difference in the sparkle of the water. I still have to add acid about every two days. So, back to the CYA issue. After getting my 98 reading from Leslie's I drained about 40% and refilled. The next month Leslie's tests again and gets in the mid 90's. I'm perplexed. So, before adding the borates I had them test again, 100. !@#!#@$. OK, so I am going to drain 1/2 and refill and then add borates. As I am draining my TF100 test kit arrives. I test the CYA and I get maybe 40. You have got to be kidding me! So I stop draining and refill and then the next day I take a sample to a different Leslie's and they test at about 40 (after the refill). I looked at their dot for myself. I came back and tested for myself and got maybe 20. Hardly any cloudiness in my samples. So I do not trust Leslie's, but I am a bit worried that the R0013 that I received may not be what it should. Is that possible/probable? I ask because we have had 100 degree full sun days and I do not seem to be losing much Cl. If I have such a low CYA in full sun 100 degree heat, wouldn't you think I would lose Cl like crazy? Maybe it's the borates? I also have a UV sanitizer. Which leads me to my last comment, I keep my Cl in the 1-2 range. Leslie's has never measured any CC. I did have 2 small algae spots back when the CYA was probably high and the Cl dropped to zero, but I was able to clear them up easily by bringing the Cl back up. I'll stop there and await any comments or questions. It may be that I should post some of this in other threads.
 
Re: Experiences of a newbie - Liquidator, borates, CYA testi

Chaddy:

Welcome to TFP! :wave:

...back to the CYA issue. After getting my 98 reading from Leslie's I drained about 40% and refilled. The next month Leslie's tests again and gets in the mid 90's. I'm perplexed. So, before adding the borates I had them test again, 100. !@#!#@$. OK, so I am going to drain 1/2 and refill and then add borates. As I am draining my TF100 test kit arrives. I test the CYA and I get maybe 40. You have got to be kidding me! So I stop draining and refill and then the next day I take a sample to a different Leslie's and they test at about 40 (after the refill). I looked at their dot for myself. I came back and tested for myself and got maybe 20. Hardly any cloudiness in my samples. So I do not trust Leslie's, but I am a bit worried that the R0013 that I received may not be what it should. Is that possible/probable?
Virtually zero chance that there is any issue with the R0013 in the TF-100. I would bet that the reagent you got with your kit is much more fresh than what the pool store was using. Pool store testing is notoriously unreliable. Here are a few examples: Inconsistency in readings. Definitely trust your test results with the TF-100.
 
Re: Experiences of a newbie - Liquidator, borates, CYA testi

Welcome.

Ditto what BoDarville said.

As far as the borate thing goes, don't get too hung up on the level. It is not the critical. Somewhere close to 50 is fine. Borates do not directly reduce chlorine usage. In your case, you had organics (algae etc.) eating up what little chlorine was available due to the high CYA. Once you took care of that, the chlorine was able to do its job. 32 oz. of bleach (depending on the %) will get you about 2 ppm for your pool and that is very normal.

When you can, sit down and practice using the TF100. Once you feel somewhat confident, post a set of YOUR results like this:

FC
CC
pH
TA
CH
CYA

Just a reminder, when doing the CYA test, have the sun to your back and add the solution to the tube. Less ambient light results in a less than actual result. If you really are at 20 CYA...you know how to get it back up and stop at your desired level. :wink:

Maybe we can see some issues contributing to your "white stuff" with some good test results.
 
Re: Experiences of a newbie - Liquidator, borates, CYA testi

It is known and well reported in The Liquidator threads that borates help reducing the white stuff problem. This is because borates act as an additional pH buffer that gets stronger as the pH rises so helps prevent calcium carbonate formation in areas of the pool where the pH rises such as in The Liquidator where chlorine is mixing with pool water. Borates also help prevent calcium carbonate scale at they hydrogen gas generation plate in saltwater chlorine generators for the same reason. It's not magic -- it's science.
 
Re: Experiences of a newbie - Liquidator, borates, CYA testi

UN1017 - Yes, I wasn't trying to imply that the borates were stabilizing the chlorine. I was thinking exactly what you posted, that the borates probably slowed down algae growth and left the chlorine to do its job. I just don't have a feel for all of these effects, so I was not expecting what I saw. Also, the white stuff is gone, but at some point I will post my results. If I do that, should I post it in the thread on that topic, or just follow up with it here? What probably would have been more useful are good results from before and after the borates, however that is not going to be possible.

chem geek - Right, that is why I added the borates, but I was not expecting to see such a dramatic change so quickly. The "magic dust" comment was tongue in cheek. I'm an engineering professor, so I assure you that I do appreciate the science. :cool:

Back to the CYA - OK, so I will trust my reagents. I will probably be adding more stabilizer, but first I would like to see how my chlorine levels react to the current chemistry. Can someone entertain the following hypothetical? Let's say the chlorine is not being used up by any organics. Yes, I know this can't be true, but bear with me. So, in 8 hours of full sun, 100F degree heat, with 86F water temperature, what would be reasonable ranges of chlorine loss solely from the sun at a CYA of 20, 40, and 60?

UN1017's comment has lead me to another question. When FC is tested does it measure all chlorine, or just chlorine that is not bound to CYA?
 
Re: Experiences of a newbie - Liquidator, borates, CYA testi

Chaddy said:
Back to the CYA - OK, so I will trust my reagents. I will probably be adding more stabilizer, but first I would like to see how my chlorine levels react to the current chemistry. Can someone entertain the following hypothetical? Let's say the chlorine is not being used up by any organics. Yes, I know this can't be true, but bear with me. So, in 8 hours of full sun, 100F degree heat, with 86F water temperature, what would be reasonable ranges of chlorine loss solely from the sun at a CYA of 20, 40, and 60?

UN1017's comment has lead me to another question. When FC is tested does it measure all chlorine, or just chlorine that is not bound to CYA?
The actual chlorine loss per day depends on multiple factors, but the chart in this post can give you a rough idea of how a higher CYA level results in a lower absolute chlorine loss even when the FC level is raised in proportion to the CYA level. The ratios in that chart are for SWG pools, but the principle is the same for manually chlorinated pools though the loss varies with the swing in FC from the manual dosing. Neither the temperature of the air nor the water make any difference in the chlorine loss rate from sunlight, but the water temperature does affect the loss rate due to chlorine oxidation of organics or anything else with which chlorine can react and that includes the slow oxidation of CYA which is probably the second largest chlorine loss in low bather-load residential pools (varies from 0.2 to 0.8 ppm FC per day depending on FC/CYA levels, temperature, sunlight exposure that produces hydroxyl radicals, etc.).

The FC test measures all the chlorine because the chlorine bound to CYA is released quickly as hypochlorous acid (HOCl) gets used up reacting with dye and then FAS reagent in the test. About half the FC gets released from CYA every 0.25 seconds if the HOCl were to get to 0 instantly so this is much faster than the timeframe of the test. So what the FC test is really measuring is the chlorine capacity, reserve, or reservoir, since most chlorine is bound to CYA. The active chlorine level that does the work of disinfection, algae prevention, and oxidation of bather waste is very low where at the minimum FC/CYA ratios for manually dosed pools the active chlorine level is the same as in a pool with an FC of only 0.07 ppm with no CYA.
 
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