Biodiesel can contain up to 10 times more water than standard petroleum diesel fuel. This excess water can end up in your fuel tank and result in numerous problems, including accelerated fuel-filter plugging, microbial contamination and icing problems in winter. Power Service recommends treating with Clear-Diesel Fuel & Tank Cleaner at least quarterly, or as needed, to remove water. Clear-Diesel also disperses contaminants and stabilizes fuel during long-term storage.