I actually know the answer to the question. We have had a little bit of rain in Texas and that led to lots of pumping water off. The pool looks great. I was noticing that my chlorine consumption was a bit higher than usual. I ran a CYA test today after I saw a 4 ppm loss. My CYA was down around 20 - might have been a little lower I ran out of tube. The dot was pretty much gone. Because I am traveling at the end of the week I decided to use liquid stabilizer to jump it up right quick. Seems like most folks have trouble with too much and mine just got up and went. The pool store guys tried to set me up with all kinds of stuff when I went in to buy the stabilizer. They actually had a heavy rain pack all ready for folks to pick up. I got out of there as fast as I could.