Review on American Marine PINPOINT Monitor Calibration by Melinda Oliver

Have been using it for many years. Outstandingly reliable and accurate. The time for building trust is over. Use API PH Test and Seachem PH Alert for months with Pinpoint Monitor. It always reads/tracks accurately. A pair of 9 volt batteries and bottles of Ph 7 and Ph 4 calibration fluids make for a quality calibration fluid. One thing I noticed when calibrating the monitor seems to be easier and faster with PH 7 PH 4. It lasted longer when used with PH 10 liquid.