A container assembly includes a container at least partially bounding a chamber and having a wall with an opening extending therethrough. A tubular stem bounds a passageway and outwardly projects from the wall of the container so that the passageway communicates with the opening. A sparger includes a tubular member having a first end and an opposing second end and an interior surface bounding a passage extending therebetween. A gas permeable sparging member is secured to the first end of the tubular member so that gas passing through the tubular member from the second end passes out through the sparging sheet. A second flange encircles and radially outwardly projects from the tubular member, the second flange being secured to the stem so that at least a portion of the tubular member is disposed within the passageway of the tubular stem.