Abstract: An electrofluidic assembly and method for its operation. The functions of a reciprocating pump and of a valve should be combined in one assembly. Here, in particular the pump and the valve should interact so that a small number of line connections are required. A pump assembly and a valve are arranged on an identical central line and use a bearing rod jointly for movable bearing of a first solenoid armature which activates a displacement apparatus of the pump assembly on one hand and a second solenoid armature of the valve which activates a group of closing bodies on the other hand. The electrofluidic assembly can be used for monitoring tank systems.