A pump-storage device comprises a treatment container including an interior separated by a partitioning board into an upper chamber and a lower chamber intercommunicating with the upper chamber via a first intercommunication port. An inlet intercommunicates with the upper chamber. A second intercommunication port intercommunicates the lower chamber with an outside. A first control valve controls intercommunication between the upper and lower chambers. A second control valve controls intercommunication between the upper chamber and a gas suction source. An actuation rod extends through the first intercommunication port. A first fixing block, a second fixing block, and a third fixing block are mounted from top to bottom in sequence on the actuation rod. An upper stop plate is disposed between the first and second fixing blocks. A lower stop plate is disposed between the second and third fixing blocks. The upper and lower stop plates are elastically supported.