CYA - High Concentration Measurement?

[BigDave]

Sounds to me that you are doing the test correctly and have no CYA. When you mix for 30 seconds - mix is shake vigorously. How's your chlorine demand? Did the FC drop to 0 over the winter? There are bacteria that consume CYA and convert it to nitrogen compounds - sometimes it takes the form of ammonia and that requires huge amounts of chlorine to clear.

[GreenThumb]

BigDave,

The winter was mild in Houston so pump cycle time was reduced and the FC often remained near zero.
I was not confident about the test method, so mixed a small amount of 'Stabilizer and Conditioner' in a 1/2-cup of tap water and let it sit for a few hours before running this CYA test.
Wow...when tested it was really cloudy. So now I better understand that this test works and that the pool indeed needs additional stabilizer.

I was unaware of the nitrogen and ammonia compund formation.

Thank you for your help.

[PoolDoc]

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