The magnesium anode & the steel container wall form a galvanic element in the water. Magnesium, as a nonferrous metal forms, the anode & provides a protective current that polarises the defects of enamelling as a cathode & thus protects against corrosion. Magnesium is consumed during this process. Magnesium anodes should therefore be checked every two years & replaced if necessary. According to DIN 4753, anodes are to be designed in such a way that their protective effect is ensured for at least two years. Per m² of enamelled inner surface, at least 0.2kg anode mass is required. The anodes can be used for all commercially available hot water tanks up to approx. 200 L capacity. Rod anode 3/4, length 700 mm.