DC-900800-1.2, Duracast 800 Gallon Plastic Water Tank | 900800 To conserve and store water safely, use Duracast’s durable plastic water tanks. These water tanks can hold 800 gallons of water and can be used for bulk storage. The polyethylene resin is FDA approved and compounded with UV stabilizers for safer, more dependable water storage. Common uses of these tanks include: temporary water supply, irrigation, rain harvesting and emergency water supply. These tanks can be used both indoors and outdoors. If keeping tanks outside, choose black or green colored storage tanks to slow the growth of natural borne algae. The natural white tanks are translucent and the better option for viewing content levels. This is a 1.2 specific gravity tank.