Abstract: A method for operating an ultrasonic measuring device, which includes: an arrangement of ultrasonic transducers for emitting and receiving ultrasonic signals along at least two signal paths through a fluid, wherein the arrangement is held by a holding apparatus having at least one wall, wherein sections of the signal paths run through at least one of the at least one wall, wherein signal path sections of at least two signal paths in the fluid are of different length; and an electronic measuring/operating circuit configured to perform the method of, in a first method step, comparing intensities of ultrasonic signals along signal paths having signal path sections of different length in the fluid and, in a second method step, determining a damping property of the fluid and an acoustic coupling property between the wall and the fluid therefrom.