Abstract: A reagent chemical is directed along a first pipe portion (20) that extends along one side of the array of wafers (14) and which contains a plurality of jets (33) for projecting the chemical toward the wafers. A plurality of second pipe portions (21) transmits an inert gas, with each pipe portion having a plurality of jets (34) for projecting the gas toward the floor of the tank.

Abstract: An open top housing is provided including upstanding peripheral side walls joined at their lower marginal portions by a bottom wall extending therebetween and further including a removable top wall provided with depending peripheral flanges telescoped over at least the upper marginal portions of the side walls of the housing with the top wall closing the open top of the housing in a fluid-tight manner. Coacting latch structure is carried by exterior portions of corresponding side walls and flanges of the housing and top wall for removably securing the top wall in the closed position and the interior of the housing includes baffles dividing the housing into separate compartments. One of the compartments includes a pressurized container of lighter-than-air gas and a second compartment includes a collapsible inflatable balloon which may be inflated by the aforementioned gas.