I don`t know if this will help but for over four years now we`ve been storing our biodiesel in a 500 gallon tank. I`d say we`ve probably gone through 4,000 gallons or so and a 500 gallon delivery lasts lasts us about six months. We`re careful to add biocide with each filling also. Never had any problems. Environmental conditions are important to consider when storing fuel. Try to keep it out of the rain and sun, although we had ours exposed on the south side of a building for three years with no adverse effects. Contact the folks you plan on getting deliveries from and ask about a minimum delivery charge and volume discounting.

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300TD W124, Two VW TDI Passat Wagons,Cummins Ram 250, Kubota Tractor
23 cylinders sipping the sweet sauce of the soy bean