I have 300 gallons of diesel in a 550 gallon above ground tank. It's 12 years old and still works fine in my diesel generator and oil furnace. I control the air flow in and out of the tank with two small check valves. One relieves pressure at 2 psi, the other relieves vacuum at 1/2 psi. The air going into the tank goes through a canister of dissicant to remove moisture. I added a quart of treatment several years ago. I live in the Pacific Northwest where we have plenty of moisture and wide temp swings.