We carry a large array of Aquatec tank pressure switches, low pressure switches, solenoid valves, and flush timers. Tank pressure switches are usually used either with a hydrollic auto shut off valve or with a solenoid valve in order to stop the incoming water from entering the pump. Tank pressure switches shut off power to the pump when the back pressure from the tank reaches a certain level. Low pressure switches are also capable of turning of incoming water when the back pressure of the unit drops below a pre-set level.