Quote Originally Posted by Watermom View Post
This is not always true. I typically open to clear water and no CYA but do not have the big chlorine demand. This has been true for my pool for many years. Not sure why, but glad!
Interesting. I wish I could say the same. No cya in the spring means lots of CL for my pool in the spring. At least thanks to the people here I now know what's going on. The first year it happened I couldn't figure out where the cya went and why I my pool was eating CL like candy!

I just had a thought....do I remember correctly you don't cover your pool in the winter? I wonder if that makes the difference, perhaps allowing the byproducts to be broken down by the sun and released into the atmosphere?