The water system tank does more than simply store water. It helps to protect the system components. A properly sized tank will provide adequate flow even when the pump is not running. It saves energy by reducing the number of pump starts. Another benefit is increased system component life due to fewer pump cycles. The water system tank consists of a steel tank containing a sealed-in-place heavy duty diaphragm which separates air from the water. The portion of the tank where water is stored is lined to isolate water from the metal tank. This protects the tank from corrosion.