My ph keeps going up?

I just got an Oakton PH1 tester and tested the 4 buckets. They all tested between 6.3 and 6.5 last night and the same this morning. I dropped the ph to 5.8 and they are holding there pretty well (some up to 5.9). Love the Oakton so far!

Yeah dude I dont think those liquid testers are any good I never used mine PH pen is where its at.. Calibrate it every month or so.