At 23:31hrs units were dispatched to the reported automatic fire alarm in the 13800 block of Stafford Point Dr. at R&R Produce. As companies were responding Comm Center advised the response was for a water flow alarm at the location. Upon arrival of Truck 21 and Battalion 21 a size-up of smoke from a 1-story commercial building was given and the incident upgraded to a structure fire. Upon forcing entry Truck 21 found pallets and associated material on fire and achieved a quick knockdown as Engine 22 secured a water supply and stretched a back-up line. With the fire quickly knocked down and searches completed ventilation was undertaken and the scene held for SFMO investigators. Upon completion of assignments all units returned to service.