Non-stainless steel tanks include tanks made of carbon steel, fiberglass, plastic or poly, glass-lined and other materials. They are available as single-walled or jacketed, with or without an agitator, and vertical or horizontal. Depending on the tank material, non-stainless steel tanks that are used for food must have a food grade coating on them. Many tanks are used for storage of water and chemicals, while some are used for melting chocolate and other confections.