An alternate system runs on the fog or great mist injected in to the intake air stream. Although several commercial systems are available, growers can assemble and install their own system using a ruthless piston pump and fog nozzles. The essential components are proven in Fig. 1. A two-stage system managed by a two- stage thermostat allows more water to be applied on excessively warm, shiny days. Temperature settings should be 5-10°F apart.
Algae development in the pads can become a problem which will decrease the effectiveness 
of the system and result in accelerated deterioration of the pads. The addition of an algaecide to the drinking water supply will help in control.
It really is desirable, especially in hard drinking water areas, to include a wetting agent to the drinking water to obtain more uniform wetting of the pads. A commercial materials or liquid home detergent at the price of 2 tablespoons per 100 gallons can be used.
Drinking water for the pads should be clean and lower in mineral content to avoid clogging and coating of the pads. A pump, pipes and gutters are used to recirculate the drinking water. A flow rate 113 gallon per minute per linear foot of pad system ought to be provided to ensure adequate wetting.
In the most typical cooling system (fan and pad), the fans draw air through wet pads that expand the length of 1 endwall or sidewall. Aspen and coated cellulose are normal pad materials that usually have life of 1 to three years. Approximately one sq . foot of pad are is needed for 20 square ft of floor area.
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