Most people are aware that water can cause rust on metals and given enough time will erode metal away, especially if the water is hot. Seems pretty simple, but people forget that a water heater is made of metal and the water inside can be extremely hot and corrosive. That’s why ALL STORAGE WATER HEATERS COME WITH ANODE RODS!
WHAT IS AN ANODE ROD?
An Anode rod, is a long rod of corrodible metal that is put into your water heater to make sure that the corrosive materials in water are attracted to it, instead of the lining of your water heater.
Imagine an anode rod much like a magnet. All the corrosive materials are drawn to the anode rod and they leave the tank alone. It is an extremely important part in your water heater, but it is designed to corrode/ wear away over time and needs to be replaced periodically.
Once the Anode Rod has worn away, your hot water is still corrosive and it will start attacking the lining of your water heater instead. Eventually your water heater will rupture (potentially causing serious flooding and water damage.)