What is the primary function of a sacrificial anode in a storage tank?

The primary function of a sacrificial anode in a storage tank is to protect the tank from corrosion. Sacrificial anodes are made of materials that are more reactive than the metal of the tank itself, typically zinc, magnesium, or aluminum. When placed in the tank, these anodes corrode preferentially, thereby sacrificing themselves to prevent the tank’s metal from corroding.

This process is important for extending the life of the storage tank, especially in environments where electrolysis could cause deterioration. The anode attracts the electrochemical reactions that would otherwise affect the tank material, thus mitigating the risk of leaks or structural failure.

The other functions suggested in the options do not relate to the purpose of a sacrificial anode. For instance, providing additional water pressure, functioning as a water filter, or measuring water temperature are not roles that anodes play in the context of a storage tank. Their sole purpose revolves around corrosion prevention, making them critical components for maintaining the integrity and longevity of the tank.