Directions: Add 1 fluid ounce for every 4 gallons of gas or diesel fuel. Allow to sit in the tank for a minimum of 24 hours before using rejuvenated fuel. Note: Keep spare fuel filters on hand. Star Tron Tank Cleaner will disperse hardened deposits and can load or clog filters. After two treatments, the fuel tank should be cleaned of all deposits and fuel filters will no longer load or clog up. After using this product to thoroughly clean fuel tanks, maintain the system with Star Tron Enzyme Fuel Treatment to prevent future carbon buildup and gumming.