Bests & Worsts Reviews from Amazon

I am a retired chemist and I highly recommend this meter. It is important to have a unit that can be calibrated. Make sure to rinse the probe with deionized or distilled water after use and always store in a 3 Molar KCl solution. The instructions for calibration are not written clearly so I recommend checking youtube for a video that walks you through the process. You can also purchase pH 7 and pH 4 or pH 10 buffers to use for calibration. The quantity of buffers than come with the meter won't last indefinetly. You can also make your own probe storege solution (3 Molar Kcl). Dissolve 225 grams of KCl in 1 liter of water or half that amount in 1 pint of water. Always use distilled or deionized water. If you are looking at pH range of 7 to 4 use those two buffers for a two point calibration. For a range of 7 to 10 use those buffers. For a range of 4 to 10 do a three point calibration with the 3 buffers. I use my meter for checking hydroponics and it has worked well