An alternate system uses a fog or great mist injected into the intake air stream. Although several commercial systems can be found, growers can assemble and install their own system utilizing a high pressure piston pump and fog nozzles. The basic components are demonstrated in Fig. 1. A two-stage system controlled by a two- stage thermostat enables more water to be applied on excessively warm, shiny days. Temperature settings ought to be 5-10°F apart.
Algae development in the pads can become a problem that may reduce the effectiveness of the machine and result in accelerated deterioration of the pads. The addition of an algaecide to the drinking water supply can help in control.
It 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 low in mineral content to prevent clogging and coating of the pads. A pump, pipes and gutters are accustomed to recirculate the water. A flow rate 113 gallon each and every minute per linear foot of pad program should be provided to guarantee adequate wetting.
In the most typical cooling system (fan and pad), the fans draw air through wet pads that lengthen the length of 1 endwall or sidewall. Aspen and covered cellulose are common pad materials that always have life of 1 to three years. Approximately one sq . foot of pad are is needed for 20 square foot of floor area.
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