A bulk material conveying system for use with a bulk material holding tank having at least one outlet. The conveying system includes a main supply line for carrying pressurized gas and a material conveying line having an inlet and an outlet. The material conveying line is in communication with the holding tank outlet for transporting the bulk material from the holding tank to the conveying line outlet. The inlet of the material conveying line is in communication with the main supply line for receiving the pressurized gas whereby the gas moves the bulk material in the conveying line towards the conveying line outlet. The system further includes an aerator line having an inlet and an outlet and at least one connector for feeding the pressurized gas into the bulk material holding tank to agitate the bulk material and push it towards the holding tank outlet and a pressure sensor for sensing when the pressure in the material conveying line exceeds a predetermined level. A shut-off valve is connected to the main supply line for establishing communication between the main supply line and the aerator line and operable in response to the pressure sensor sensing the exceeding of pressure for shutting off flow of the pressurized gas from the main supply line to the aerator line thereby increasing gas flow to the material conveying line for eliminating buildup of bulk material in the material conveying line.