An arrangement, comprising - a device for determining and/or monitoring at least one process variable of a medium in a container with a protective tube, said protective tube comprising a tubular, in particular cylindrical, element, and with a measuring insert, which is used to determine and/or monitor the process variable and is mounted in the protective tube, - and a container with a medium arranged inside it, wherein the tubular element is attached to the container in such a way that the tubular element at least partially protrudes into an internal volume of the container, wherein the tubular element has an inlet opening and an outlet opening, said inlet opening and outlet opening being arranged on opposite sides of the tubular element, wherein the inlet opening and/or the outlet opening is/are arranged and/or configured in such a way that the medium flows around the measuring insert, wherein the outlet opening is arranged in a first end area of the tubular element, said first end area facing toward the medium, wherein the inlet opening is arranged in a second end area of the tubular element, said second end area facing toward the container, characterized in that the protective tube is installed in the container from below in such a way that an included angle between the vertical direction and a longitudinal direction of the protective tube extending from the first end area to the second end area is between 0° and 90°, so that the inlet opening at the second, in particular proximal, end area of the tubular element is arranged below the outlet opening at the first, in particular distal, end area of the tubular element, so that any gas bubbles produced rise in the protective tube and escape from the protective tube through the outlet opening. - a device for determining and/or monitoring at least one process variable of a medium in a container with a protective tube, said protective tube comprising a tubular, in particular cylindrical, element, and with a measuring insert, which is used to determine and/or monitor the process variable and is mounted in the protective tube, - and a container with a medium arranged inside it, wherein the tubular element is attached to the container in such a way that the tubular element at least partially protrudes into an internal volume of the container, wherein the tubular element has an inlet opening and an outlet opening, said inlet opening and outlet opening being arranged on opposite sides of the tubular element, wherein the inlet opening and/or the outlet opening is/are arranged and/or configured in such a way that the medium flows around the measuring insert, wherein the outlet opening is arranged in a first end area of the tubular element, said first end area facing toward the medium, wherein the inlet opening is arranged in a second end area of the tubular element, said second end area facing toward the container, characterized in that the protective tube is installed in the container from below in such a way that an included angle between the vertical direction and a longitudinal direction of the protective tube extending from the first end area to the second end area is between 0° and 90°, so that the inlet opening at the second, in particular proximal, end area of the tubular element is arranged below the outlet opening at the first, in particular distal, end area of the tubular element, so that any gas bubbles produced rise in the protective tube and escape from the protective tube through the outlet opening.