a print - washing tank with generally rectangular spirally - looped pipes in parallel vertical arrays , fed by a horizontal input conduit in the upper portion of the tank , the arms of the pipes having holes to spray photographic prints on both sides with jets of water , the prints being supported between the vertical spray loops , using either wire baskets or being supported directly in the narrow vertical spaces between the spirally looped pipes . a drain pipe array is provided at the bottom of the tank , having a plurality of widely spaced intake ports and leading to a vertical siphon exit conduit near the back wall of the tank and which may be either inside the tank or may be located externally . the top loop of the siphon drain system is located slightly below the level of the water input pipe .