An apparatus for conveying thick matter has a drive cylinder for receiving hydraulic fluid, a drive piston, which is arranged in the drive cylinder, a conveying cylinder for receiving thick matter, a conveying piston, which is arranged in the conveying cylinder, and a piston rod, which is fastened to the drive piston for coupling motion together with the conveying piston. The drive cylinder has a rod-side opening for applying pressure to a rod side of the drive piston by way of hydraulic fluid and a crown-side opening for applying pressure to a crown side of the drive piston facing away from the rod side by the hydraulic fluid. A drive pump is designed to generate a drive volume flow having a drive pressure of hydraulic fluid for moving the drive piston. A pump connection is designed for variable connection of the drive pump to the rod-side opening or the crown-side opening for the flow of hydraulic fluid. A sensor is designed for automatic detection of whether the pump connection is connected to the rod-side opening or the crown-side opening. A control unit controls the apparatus in a rod-side operating mode, when the rod-side pump connection is detected, and in a crown-side operating mode, when the crown-side pump connection is detected.