Abstract: An apparatus for cleaning a rounded tank such as the tank of a gasoline tanker has a pivoting coupler between its handle and the base its cleaning head. In this embodiment the base of the head is formed with lugs which receive a tongue. The tongue is formed on an end of the pivoting coupler. A pin traverses corresponding holes in the lugs and pivoting coupler in order to allow the pivoting coupler to pivot relative to the head. Further embodiments include a water supply tank mounted to the handle and a pump arranged to urge water from the tank through a conduit out through the head of the cleaning apparatus.