Last fall I tested CYA and it came in at over near or over 100. Just tested to start getting ready to open and I have a CYA of...well near zero. I filled the tube to the top and could still easily see the dot. We've had a significant amount of rain as the pool is near the top at this point and needs some drained out. I'm just wondering if such a significant drop normal over winter or is it possible my reagent is bad, less then a year old purchased last Aug or so.
Thanks
Matt
Thanks
Matt