The Clean Green Recirculation Systems are designed to completely clean the entire fuel storage tank. Multiple passes allow the system to clean the fuel to International "A" grade standard, killing the spores of the bacteria, fungus and yeast so fuel bug will not continue to grow. Systems start at 500 liters per hour up to 48,000 liters per hour and incorporate our Vortex vertical tank system, our Sweep Surge horizontal tank system and our Recharge Series of fuel tank breathers. All Clean Green Recirculation Systems come with the Clean Green Limited Guarantee of "A" grade fuel or better.