I can't figure out why this is happening. When I test the pH I will get a low reading (today's was 7.0) followed by a retest to verify, because 7 didn't jive with the reading from last time, and I get 8.0. I bought new reagent about a month ago and I have soaked my test tube in bleach to remove some cloudiness.
I generally test FC/CC first then rinse the tube and do pH. Any ideas?