Quote Originally Posted by Donna's Poolboy
I thought "tied up" chlorine was the same as "combined chlorine."
You are right, the term does seem to imply "Combined" however his statement read "However, there is also chlorine "tied up" in the CYA" so, trying to keep the comparison of apples to apples per se, I followed suit. Sorry for the confusion. I would always refer to CC as Combined since technically it is not "tied" up but "used" up.

Dave