The HI9814 is a slim, lightweight, and waterproof portable meter that measures the pH, conductivity (EC), total dissolved solids (TDS) and temperature of nutrient solutions used in hydroponics, aquaponics and greenhouse growing. The meter operation is simplified with only two buttons. One is used for turning the meter on/off and for calibration while the other is used to switch between the measurement modes. The HI9814 has advanced features including a selectable EC to TDS conversion factor (0.5 - 500 ppm and 0.7 - 700 ppm).