What is the threat for your Water Heater Tank? A hot water heater tank is made from metal. Metal is gradually destroyed by the oxygen in the water. This electro-chemical process is called oxidation. Plastic or enamel coating of the tank’s inside is no effective protection. No production process ensures crack-free coating. In short, corrosion destroys the metal parts of your water heater tank until it fails and needs to be renewed. Magnesium vs. Aluminum/Zinc Anodes Magnesium is superior to aluminium and zink. Zinc’s surface quickly oxidates and prevents an effective functioning. Magnesium is electrochemically more active and attracts more harmful action. It is not toxic while aluminum can disturb a large number of biological processes in the human body. How to extend the Anode Life To extend the anode life, and as an effect, your water heater’s life; drain water from tank whenever your RV is not in use, avoid any extended time of non-use with water in tank, flush the tank on a regular basis, replace the anode rod every year or when 75% or more have worn. Take action and avoid high expenses for the renewal of your water heater.