The Aqua Medic mV Computer-Set uses the same microprocessor technique as the Aqua Medic pH Computer-Set. Waterproof touch keys are used to set the required values and calibrate the electrode. The Aqua Medic mV Computer-Set is ideal for controlling anaerobic biological filters such as the Nitratereductor which have negative redox potential or can control the supply of ozone to the aquarium, or monitor the aquarium waters redox potential. All these functions are possible due to the computers broad measurement and control range of -500 to +1000 mV. The direction of control can be set upwards or downwards. The status of the direction of control and the output are shown on LEDs. A plastic shafted mV electrode with a BNC fitting and calibration fluid is included.The redox potential or oxydation-reduction potential (ORP) is an electric value that is a parameter for oxydation and reduction process in the water. The redox potential is of special interest in the aquarium:To check the water qu