Review on 🟡 Alysontech Digital pH Meter: High-Precision Pocket Water Quality Tester (Yellow) by Mike Rubenstein

So here is the missing (explicit) calibration instructions first: 0. Mix 3 calibration solutions as directed, be as accurate as possible1. Dip the tip of the pH meter into the calibration solution2. Press and hold the CAL3 button. Count 5 seconds (one Mississippi, two Mississippi, etc.) and release the CAL4 button. Only then should you see the correct calibration value (4.00, 6.86 or 9.18) flashing 3 times on the display. assumed my meter was broken before realizing it was user error. And just a quick refresher in the Chem 101 lab for us seniors: be as clean and accurate as possible when making calibration solutions. Use distilled water, measure by weight if possible (remember 250ml = 250g), remove ALL powder from packaging, stir until fully dissolved. The accuracy of your meter depends on the accuracy of your calibration solutions.