I'm using a Lamotte ColorQ tester currently. So, it is a digital reading. I'm not sure how accurate the CYA readings are. I'm pretty sure the zero was a false reading. But, I'm positive that I have lost CYA over the past month, because it was reading 40-50 all my testings before my CC trouble occurred.

I did order the Taylor kit recommended here, but I will not receive it for a few more days.