Sacrificial Magnesium pole for hot water heater

In addition to replacing the plastic plug yearly, I would also buy one of these and flush the wh 1-2 times yearly to remove the crud. Putting 1 gal of generic white vinegar per 15 gal of water into the fresh water tank then pump through all the water lines until you smell the vinegar, let sit overnight, will also help before flushing the tank with the rinser. Loosens up and dissolves the calcium/lime in the water.

Water Heater Tank Rinser