Water heaters have an anode rod that prevents the tank from corroding. If you replace it every few years, it will extend the life of your water heater from ~10 years to potentially 25+ years.
Water heaters use an anode rod to attract and remove sediments from the water being heated. An anode rod will corrode and deteriorate over time until it’s no longer capable of functioning and has to be replaced. This part literally sacrifices itself to keep the tank in optimal condition. That’s why it’s also referred to as a sacrificial anode. Without it, the water tank would start corroding from the inside out which would eventually result in a severe leak at the bottom.
After the anode rod deteriorates, the tank will begin corroding. This is the reason water heaters typically only last 5-15 years. If you replace the rod every few years (cheap and easy), it will extend the life of water heater by decades.
