Reddit mentions of U.S. Solid Anode Rod- 9" Long Magnesium Anode Rod for Hot Water Heaters,3/4" NPT Thread Prevent Corrosion Within Your Water Heater, Sacrificial Anode Rod for Suburban Hot Water Heaters, a Product

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CHECKING YOUR ANODE ROD: The anode rod should be removed from the water heater’s tank annually for inspection and replaced when more than 6” of core wire is exposed at either end of the rodMAGNESIUM: Based on the electromotive series of metals we know that magnesium will corrode before the steel in your hot water tankWATER HEATER: Hot water tanks are made of steel which is very corrosive when exposed to water; The inside of water heaters are coated with porcelain to prevent the steel from being exposed to water; There are always small cracks in the porcelain that can allow water to meet with steelLIFESPAN: The anode rod is corroding faster than the steel in the tank; You should replace your anode rod every 3 to 5 years so the life of your hot water tank isn’t shortenedSATISFACTION GUARANTEED: All U.S. Solid products come with a 1 year satisfaction guarantee; If you have any questions or issues with your product, contact our customer service team; A representative will be more than happy to assist you