The pH computer-Set utilises a modern microprocessor, which provides high precision measurement and control. The pH computer-Set is 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. A plastic shafted pH electrodewith BNC fitting and the correct calibration fluids are included.