Carefully measure the amount of water required to bring water back to original level. This is the amount of spray mix that the sprayer will apply per acre at that speed and pressure. If you find this is not the desired amount of pesticide recommended to be applied, change the rate of application and recheck. Small adjustments in rate of application can be made by changing the pressure. Lower operating pressure reduces the volume of spray delivered.
High pressure increases the volume of spray delivered.
A change in ground speed is the easiest way to obtain a small change in application rate. Faster ground speed decreases the volume applied per acre. Slower ground speed increases the volume. For a major change in the application rate, change the nozzle tip size. Larger tips increase the volume, smaller tips decrease the volume.