An alternate system runs on the fog or great mist injected into the intake air stream. Although a number of commercial systems can be found, growers can assemble and install their own system utilizing a ruthless 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 employed on excessively warm, shiny days. Temperature settings ought to be 5-10°F apart.
Algae growth in the pads may become a problem that will decrease the effectiveness of the system 
and lead to accelerated deterioration of the pads. The addition of an algaecide to the 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 additional uniform wetting of the pads. A commercial materials or liquid household detergent at the rate of 2 tablespoons per 100 gallons can be used.
Water for the pads should be clean and low in mineral content to avoid clogging and coating of the pads. A pump, pipes and gutters are used to recirculate the water. A flow rate 113 gallon per minute per linear foot of pad program should be provided to guarantee adequate wetting.
In the most common 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 common pad materials that usually have life of one to three years. Approximately one square foot of pad are is necessary for 20 square foot of floor area.
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