Abstract: A system for converting powdered detergent in a shipping container into a concentrated detergent solution and for maintaining a predetermined volume of the solution available for use by a remotely located washing apparatus. A chassis defines a reservoir suitable for holding concentrated detergent solution and has an inlet port opening into the reservoir. A curved screen member is continuously mounted across and extends into the open mouth end of a detergent-filled container. A cradle assembly pivotally positions the container and screen in inverted position over the inlet port to the reservoir such that the curved screen retainably supports the detergent within the container. A single nozzle is mounted at the inlet port for uniformly directing a spray of solution from the reservoir against substantially the entire downwardly facing surface of the screen, dissolving a portion of the detergent carried thereby, which passes in solution through the screen and into the underlying reservoir.