The rate per 100 gallons is pure nonsense for any pesticides. Use the rate per acre. In Canada, I use 4-5 kg per hectare which would come out to 4-5 pounds per acre. That’s the rate you want to apply regardless of water volume. You may want to use Kumulus instead of micronized sulfur as it is easier to handle and is easy to dilute (and stinks less). The sulfur is dispersed in water, not diluted. It falls to the bottom of the tank rather quickly should you stop the treatment for any reason. If that happnes, make sure to mix your tank thouroughly. A bit of high pressure washer to the bottom of the tank will do wonders…