Quote Originally Posted by chem geek View Post
This is a typo and is reversed. For every 10 ppm FC added by Trichlor it increases CYA by 6 ppm. For every 10 ppm FC added by Dichlor it increases CYA by 9 ppm. Between Trichlor and Dichlor, it is the latter that raises CYA more quickly.
whoops! that's what I get by answering posts at 4:30 in the morning!