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.