DON’T DRINK WATER FROM A HOT WATER HEATER. The most common “anode” that they use to reduce tank corrosion is aluminum. In other words, an aluminum rod hangs in the tank and releases positive ions (aluminum ions) to reduce the rate of corrosion of the steel tank itself. Bad idea in general, but especially bad if you drink it, and especially double bad if you have fluoridated water. Probably a great way to get alzheimers.