I chose to place two spray heads at each level. The best type of spray head is the 'misting' type which will deliver a cloud of fine water droplets to the sprouts. The next best head is a fine 'mini spray'. I chose to use a 180 degree spray head on each side.

One tray of sprouts is shown. The water distributes evenly throughout the box during the watering cycle. Lower trays get a rain like effect from the upper trays.