Test strip based testing for CYA is horrendously bad. The computerized readers pool stores often use are a little better than eyeballing the strip, but not good enough to provide very useful results.

If you want us to help you, you are going to need get a K2006 . . . and use it. Otherwise we're all flying blind.

You have to understand that accurate testing HURTS pool stores, because good testing results in large reductions in chemicals sold. A few stores go to the trouble of testing accurately, but it's hard to expect them to spend time and money on activities that they can't sell (testing), when doing those things (testing) well will REDUCED their sales on things that do bring them income.

Test strips are easy. Everybody likes easy. And until you have the K2006 (or some of the more expensive alternatives) you'll never realize how much easy -- but bad -- testing hurts you.