I had this same issue last year with my trusty K2006 test kit. I initially thought it was my reagents, but when I replaced them it persisted, last year and now this year too. The kit & reagents are stored indoors all year round.

When I test the pH, instead of a yellow to red/blue range for the test sample, I am getting an off-orange color that doesn't correlate with any of the color chips in my kit. I can't determine what my pH really is - I am assuming around 7.4. The odd thing is when I use my Rainbow daily kit, I am getting the right color range.

I haven't had any issues with the chlorine, alk or hardness tests. Has anyone else had a similar issue?

I'd like to post photos taken Sun 6/3 that illustrate this anomaly, but I am not sure how to do it on here - I have them on my hard drive.

Thanks in advance for your advice & comments.