TDS Meter Digital Water Tester, Jakeloo 4-in-1 pH TDS EC Temp Water Tester for Drinking Water pH Meter for Water Tester High Accuracy, Ideal for Pool/Aquarium/Water/Wine (Red3)

How to Calibrate the pH pen? The orp meter for water should be calibrated before use, and the measurement accuracy will be higher. 1. Before calibration, put the pH 4.01/ 6.86/ 9.18 buffer powder into 250 ml of water and stir well 2. Turn on the on/off button, and adjust to pH mode 3. Put the probe into the pH 4.01 reagent, and press and hold the CAL/MODE button for 6 seconds, then you can see corresponding value flashing 3 times which means calibration of pH is completed. The pH6.86/pH9.18 calibrate is the same way. 4. After each calibration, the probe should be cleaned and wiped clean before proceeding to the next reagent calibration ORP Pool Tester Package Includes 1 x 4-in-1 pH Meter 1 x Carrying case 3 x pH buffer powder 1 x User's manual Notes Clean the electrode with distilled water Every time before and after use, gently wipe it with a clean, soft cloth when you're done before capping it again. Be sure to add water according to the required ratio, otherwise it will affect the accuracy of the calibration and increase the error.