It is frequently thought that the greater the potential difference between two metals, the greater the likelihood of galvanic corrosion. However, it is the magnitude of the current density between them that determines the metal loss. Hence, a large cathode and a small anode will result in a large corrosion rate due to galvanic coupling. Galvanic corrosion can be prevented, or at least minimised, by making the anode much larger than the cathode (100 times greater area or more).