I just acquired 200 used 55gal steel drums in great shape for $5 each. My plan is to store VWO in about 1/2 of them and off road diesel in the rest. What additives should be used to preserve the two different fuels? The drums will be stored on a concrete slab in an uninsulated barn. Here in the Northwest, temperatures seldom dip below 0 degrees in winter and summer heat can reach 90 degrees (F) for five days or more in Summer. Thanks in advance for the help.