Abstract: A sacrificial metal anode device incorporating a resistor assembly into the construction of the sacrificial anode is insertable into a metal water storage tank. The metal water storage tank designed to contain heated water is thereby protected from corrosion by the sacrificial metal anode. The sacrificial metal anode device comprising an elongated metal anode member with a metal wire core, an insulating sleeve secured over the elongated metal anode member wherein said insulating sleeve has an external wall with threads to fixedly secure a metal cap. The metal cap having threads on an internal wall to fixedly secure the insulating sleeve further including a cylindrical receptacle for receipt of an end of the elongated metal anode member and an electrical resistor assembly.