So I am so confused. A few years ago I had an issue with the CYA in my pool being way too high and the only solution was to drain most of the pool and start again. At the time I was using chlorine tablets in a chlorinator. Being on this site I learned that those tablets have CYA in them and that's why there was so much in my pool. I started using this system to care for my pool and it has been awesome ever since. But here is where I get confused...I closed the pool last year with a CYA level of 35. We just opened the pool on Tuesday and now my CYA is too low to detect with my test kit. I added chlorine tablets the chlorinator in an attempt to raise the CYA level, because I had them and I really don't want to go out and buy stabilizer. Do you think the tablets will be enough to raise the CYA level? How did the CYA drop so much while the pool was covered? Is is just from the draining of the water below the skimmers and then the refilling of that foot of water?