Ducks may be raised on litter or on wire or on mixed litter wire systems. Nipple waterers are preferred over cup waterers to reduce water spillage on litter or into the waste pit. Waterers are best placed over wire flooring to prevent litter from becoming excessively wet under the waterers. It is important to prevent litter flooring from becoming excessively wet and becoming anaerobic, as this can lead to strong odors that can annoy neighbors. Two methods to do this include adding litter to the barns daily and venting excess heat from the brooder barns through the grower barns to pick up moisture and cause the temperature dependent fans to turn on. Ventilation fans should have hoods on them which point towards the ground as duck operations produce significant dust. By reducing the dust, the odor is reduced. Wire floor systems, with liquid manure storage under the wire, support higher bird densities and efficient production but can lead to odor complaints from neighbors.