Microprocessor controlled pH monitor and controller The pH computer-Setutilises a modern microprocessor, which provides high precision measurement and control. ThepH computer-Setis used to control precise values of pH in the aquarium or the Calciumreactor. The computer can switch up to 500 watts using the supplied external electrical socket. When the calibration key has been selected the unit will automatically calibrate itself to the electrode. Aplastic shafted pH electrodewith BNC fitting and the correct calibration fluids are included.