I need some help with a CYA reading I can't seem to figure out.
Opened the pool this spring and the CYA was 120. Pool store recommended a product that would reduce the CYA. We live on a well and having enough water trucked in would cost about $900 so we figured we would give the kit a try. After 3 weeks it sort of worked as the CYA came down to 110.
Later in the year I decided to buy a TF-100 kit so I could do a SLAM. I also took a sample to the pool store. All my readings were pretty much spot on with the pool store so I felt confidant all was good. I did the SLAM and all went well (over 40gal of bleach with such high CYA but it is still cheaper than $900 of water then a SLAM).
Two days after the SLAM finished we had a hurricane set to come through. I decided to take advantage of the 3"-6" of expected rain so I drained the pool 9" and figured I would fill the remainder with the hose. The hurricane came through and dropped 4". I was using the hose to fill when more rain arrived that week and filled the remainder of the pool. I did some math on pool size, volume, and CYA level and I calculated that the CYA should be at 90 after the drain and refill. I did a test and boo ya - the CYA was at 90. So the drain/refill worked and I can do math correctly!
But then it just kept raining. Everyday we had the threat of heavy rain and pretty much every day it rained. Over the course of 20 days we got over 17" or rain. Had I known we would get that much rain I would have drained the pool in advance again to lower the CYA more efficiently. In total I had to remove excess water from the pool about 3 times equating to about 6" of total water removal (though this water was diluted, drained, diluted, drained, etc). So again I did some quick math and calculated at BEST I would be at CYA 81.
I used the test kit and got a CYA of about 50. Not understanding, I completely did the test again and got around 50 again. I tried a third time with the same result. So we took a sample to the pool store and they calculated 84 which is in line with my calculations. It was a bir cloudy so I figured maybe that was the problem.
Days later I tested when it was sunny out and got about 50. Went on vacation for a week, came back, tested and got about 45-50. I dumped the solution in the bottle and re-read the results 3 times and each time I got about 50.
Why is my reading so off? It cant be the pool store as I was able to match their numbers earlier this year AND the math does not justify the CYA doping that much. We simply did not remove enough water to be at 50 yet. I have read the CYA test instructions, tried different angles, tried glancing at it, etc.
Opened the pool this spring and the CYA was 120. Pool store recommended a product that would reduce the CYA. We live on a well and having enough water trucked in would cost about $900 so we figured we would give the kit a try. After 3 weeks it sort of worked as the CYA came down to 110.
Later in the year I decided to buy a TF-100 kit so I could do a SLAM. I also took a sample to the pool store. All my readings were pretty much spot on with the pool store so I felt confidant all was good. I did the SLAM and all went well (over 40gal of bleach with such high CYA but it is still cheaper than $900 of water then a SLAM).
Two days after the SLAM finished we had a hurricane set to come through. I decided to take advantage of the 3"-6" of expected rain so I drained the pool 9" and figured I would fill the remainder with the hose. The hurricane came through and dropped 4". I was using the hose to fill when more rain arrived that week and filled the remainder of the pool. I did some math on pool size, volume, and CYA level and I calculated that the CYA should be at 90 after the drain and refill. I did a test and boo ya - the CYA was at 90. So the drain/refill worked and I can do math correctly!
But then it just kept raining. Everyday we had the threat of heavy rain and pretty much every day it rained. Over the course of 20 days we got over 17" or rain. Had I known we would get that much rain I would have drained the pool in advance again to lower the CYA more efficiently. In total I had to remove excess water from the pool about 3 times equating to about 6" of total water removal (though this water was diluted, drained, diluted, drained, etc). So again I did some quick math and calculated at BEST I would be at CYA 81.
I used the test kit and got a CYA of about 50. Not understanding, I completely did the test again and got around 50 again. I tried a third time with the same result. So we took a sample to the pool store and they calculated 84 which is in line with my calculations. It was a bir cloudy so I figured maybe that was the problem.
Days later I tested when it was sunny out and got about 50. Went on vacation for a week, came back, tested and got about 45-50. I dumped the solution in the bottle and re-read the results 3 times and each time I got about 50.
Why is my reading so off? It cant be the pool store as I was able to match their numbers earlier this year AND the math does not justify the CYA doping that much. We simply did not remove enough water to be at 50 yet. I have read the CYA test instructions, tried different angles, tried glancing at it, etc.