Yikes, I pulled open a corner of my pool cover off and took a sample to quickly test PH and TA from my 23K G gunite and was shocked to see my TA test go red after ONE DROP!

The PH was 7.0, which is the lowest I have ever seen it since the pool was replastered five years ago. I usually have problems with PH and TA being too high, but last season I was having some PH and TA bounce issues which I thought I had under control.

I'm in the process of bring the TA back up now, but can anyone speculate on why the TA would crash from a normal reading in the late fall after it was closed for two months (I forget exactly, but it was fine) to something below what the test kit could measure?