There are many brands to consider when it comes to PH meters and or EC meters. Here at HTGSupply we carry the best, Hanna Instruments and Bluelab. These companies have proven themselves to be worthy of the hydroponic industry. Many inferior pH meters require constant calibration; this is time consuming and does not have to be. Hanna and Bluelab hold their calibration making them very user friendly. Hydroponic growers will enjoy a few nice features you will just not find with inferior pH meters. Rest assured the meters HTGSupply carries are quality units that will last. Only trust your precious hydroponic crops with Bluelab or Hanna pH meters.