Quote Originally Posted by waterbear View Post
It's really as good as it gets. Believe it or not the colorimeters used by some pool stores actually have less precision (+10/-25 ppm) on this test than the 'disappearing dot" and they are better then any home colorimeter
Yeah, I've gotten some pretty wacky results from pool store testing. I think I'll go ahead and get the newer kit that uses a small sample size and less reagent; over time it'll save me some $$ and hassle reordering reagent.

Thanks again for your help.