How much de is needed for 3600 gallons of water?

The amount of diatomaceous earth (DE) needed for 3600 gallons of water depends on its intended use, such as for filtration or pest control. For pool filtration, a general guideline is about 1 pound of DE per 10 square feet of filter area. For pest control or gardening, typically 1-2 cups of DE per 100 gallons of water is recommended. Therefore, for 3600 gallons, you would need approximately 36-72 cups or 9-18 quarts of DE, depending on the application.