An outlet aperture arrangement (100) includes a flow promotion device (10) which, in use, is located at an outlet aperture (12) defined by a liquid container (14), for example, a toilet cistern. The device (10) includes a divider arrangement (16). The divider arrangement (16) includes one or more divider members (18). In use, the divider arrangement (16) is located at or in an entrance (20) to the outlet aperture (12), so that the or each divider member (18) divides the entrance (20) into a plurality of outlet entrance parts (22).