SHAPURE 0.01 PH High Accuracy Water Quality Tester with 0-14 PH Measurement Range, TDS Range 0~9990 ppm, Accuracy: ±2%. for Drinking Water, Aquarium, Swimming Pools Combo Pack TDS Meter & Digital pH Meter

How To Calibrate pH Meter? ? Turn on the pH meter ? Dissolve each buffer solution in 250 ml of distilled water ? Immerse the electrode into the pH 6.86 solution gently stir and wait over 5 minutes. (Under Room temperature) ? Press the "CAL" button to see the displaying number going to 5 then release, to find 6.86 calibration point. The display will Start Flashing 6086 and wait until the display stops flashing. ? Rinse the electrode with distilled water and make it dry with filter paper. ? Repeat the above steps with other pH buffer powders.