CYA, Chlorine, and Pool Pilot Problems

Jul 4, 2013
13
Southcentral WI
We installed a new AG pool this July and filled it on July 24th.

Problem 1 - We purchased the Pool Pilot Digital 220 swg and started it about 3 days ago. I was adding liquid chlorine until then (just liquid chlorine or bleach, nothing else from the pool store thanks to this forum). I added enough chlorine to get 3ppm before starting the swg. When I tested the chlorine the next day, it was low (less than 1). So I put it in a 24-hour Boost just to make sure it was working. This morning (around 9am), the reading from my Taylor K-2006 read 3.8ppm chlorine. About 4 hours later, I brought my sample into the pool store to confirm my CYA (more on that later) and they read 0.3 CC and 0.0 FC. I came home and tested the water again with the Taylor kit and I got 0.5 FC and 0.0 CC. Our water is crystal clear and has been since day 1. We have only swam in it twice due to the unseasonably cold weather and rainstorms in Wisconsin. The pool temp has been 75 degrees or less everyday. Why did we have such a dramatic drop in chlorine in 4 hours?

Problem 2 - We added about 360 lbs of salt per the recommendation of the pool store (actually we added 80 lbs less than they recommended). The salt was added many days before hooking up the swg. We scrubbed the salt around well with a broom and went swimming briefly to mix it up. The Pool Pilot states that we have 3300 ppm of salt, but the pool store today said that we have 2300 ppm. Why would there be such a huge discrepancy?

Problem 3 - The electrician set up the Pool Pilot Dig-220 for a 110v conversion. During the initial set up, I set the Purifier for 50% and the cell at level 2. When I read the volts/amps, it showed 31v, 5.9a. When in boost mode it's 31v 6.5a. I changed the setting to 75% and now it reads 31v 6.3a. Is that voltage too high?

Problem 4 - The temperature in the pool appears to be 2-3 degrees colder than the temp that the Pool Pilot is reading. I manually adjusted it on the Pool Pilot. I assume this isn't a big deal unless I hear otherwise from someone.

Problem 5 - I can't determine my CYA. The pool store initially showed it at zero on 7/30. Today they showed it as 45. I have tested it with my kit twice (once today) and both times I haven't been able to test for any CYA. The black dot never disappears, although the test only goes down to 30. I have ProTeam UV Shield to add to the water. Should I assume that I currently have 45ppm and add whatever the pool calculator instructs me to do? When Pool School says to add the solid stabilizer with a sock in the skimmer basket, does that mean a skimmer sock?

Here are my numbers from my K-2006 kit:

FC- 0.5
CC- 0.0
pH- Higher than 8.0 (it took 9 drops of acid demand agent to get pH to 7.2)
TA- 300 (I received the same number 2 days ago)
Calcium Hardness- TBD (the sample never turned red, so I need to research this some more)
CYA - less than 30, possibly zero?

Here are the pool store numbers:

FC- 0.0
CC- 0.3
pH- 8.1
TA- 210
Calcium Hardness- 375
CYA- 45

My pH has been high for over a week. I've been adding Muriatic Acid periodically. I added more today. I am aware that adding Muriatic Acid over time to lower pH, then aerating the water repeatedly should bring down the TA. If there is anything else I'm missing on that, please let me know.

Please help! I have spent many hours on this AWESOME forum but I can't find answers to my specific situation. Thanks!!!

Keri
 
Have you added anything to the pool that has CYA in it? (Trichlor, Dichlor, Stabilizer, etc.) If you haven't then you can assume that the CYA is truly zero. I would trust your testing anyway.

I would add about 3/4ths the amount that the pool calc tells you to add and test it again in a week.

Add as much muriatic acid as needed to get the pH down between 7.2 and 7.8. It may take more than the PC tells you. If it doesn't come down to the target just add more.
 
Hi, how much pro-team or CYA have you added to the pool so far, and how long ago was it added? When you add CYA you can put it in an old gym sock or a length of panty hose, tie it off and hang it in front of the return. Give it a good squeeze a couple of times a day until it is all dissolved.

MA will bring down TA and pH and you aerate to raise the pH. TA is only important to regulate pH drift. Your SWG will cause pH to rise. That along with the high TA means you don't need to aerate to raise the pH, it will drift up on its own. Try to keep pH at 7.5 - 7.2 and your TA will drop as well.
 
Thank you both for your replies! I haven't added any stabilizer yet. The only products that I've added are bleach, muriatic acid, and liquid chlorinator (see pics below) that the pool store assured me was only liquid chlorine.

Thanks for the info about the swg raising the pH! It's good to know that I can keep adding MA to get the pH and TA down without needing to aerate.
 

Attachments

  • 20130809_155820.jpg
    20130809_155820.jpg
    170.1 KB · Views: 50
  • 20130809_155814.jpg
    20130809_155814.jpg
    179 KB · Views: 50
I added 6.5 lbs of cyanuric acid (a little less than 75% of the PC's recommendation) into two socks, then I put the socks in pantyhose and dangled it in the water over the return. Two questions: first, can we swim while the CYA is still dissolving in the water? and second, I'll leave the pump running for 24 hrs, but after that while the pump isn't running, the socks will be touching the pool liner/wall while they just hang in the water, is that okay on the liner?

As always, thanks!!!
 
akapril6 said:
I haven't added any stabilizer yet.

That answers the question about your SWG and why your chlorine was dropping so fast. With zero CYA you had zero protection from the sun. Your SWG is unable to overcome the loss rate from that by itself.

Your next step should be to get your PH down to 7.2, raise your FC to shock levels per cya chart (12PPM) and do an OCLT. I say this because you have been running low FC with your rapid UV loss. Best to do it now, find out if your passing before you raise your CYA to the recommended levels for SWG pools.


(Only use liquid chlorine/bleach to raise your FC to shock levels and turn off your SWG during the OCLT test)
 
Scott, thanks for the tip. I did the OCLT test last night/this morning and I passed. I must have been a bit surprised because I took the FC test three times this morning. My chlorine did go down but only by 0.8 ppm. My pool was still full of chlorine at 6:30am! I will continue to keep my pH down and squeezing the CYA until it's fully dissolved.

It needs to be said that I'm so disappointed in our local pool store. I have been there three times, and they have never mentioned adding a stabilizer. I have had my water tested every time and have only purchased MA and liquid chlorine from them, nothing with stabilizer in it. During my last visit, when they registered no chlorine and I explained that I had 3.8 ppm 4 hours earlier, they still never mentioned CYA! I was the one who asked to purchase it due to this forum and because it was mentioned in the Pool Pilot manual as a recommended option. How does everyone else manage their pools without the assistance of this forum??? Thank you to everyone who posts their opinions and suggestions on here!!!!

I will certainly support this site because it is invaluable.
 
Wait a week after the CYA dissolves before testing it again. It'll be doing it's job but may not show up on the test and there's no use wasting reagent.

You'll notice that the swg does a much better job now that you have some CYA in there. You'll probably have to turn it down.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Keep in mind, the person behind the counter doing water tests is probably not trained in water/pool maintenance directly. Just some person that was trained to work in the store, and shown how to run the testing machine. They don't need any understanding of the what's, the why's, and the how's because the machine spits that all out on paper.

What I would be disappointed in, is how they managed to get a 45 CYA reading on a fresh fill with nothing added to raise it.

1 thing to add before you start using reagent to test CYA, is you should decide since it's kind of late in the season how high you want to take your CYA and how much you want to depend solely on your SWG and how much you want it to run. At 30 CYA you might find your SWG needs to have a longer run time, and/or higher output to keep up with chlorine loss from sun light. With higher CYA at 60 which is recommended for SWG pool you would find your run time and/or output can be lower.

Do you have or plan on getting a solar cover? That will lower your chlorine loss during the day more if you do.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.