 What's my best way to store them for the fuel? Full, empty tanks? I know I'm going to put some treatment into them. The manuals from the pump manufacturer are kind of vague on it, so I was looking for a little direction. If it's a metal tank or has metal components in it, you want the diesel fuel to be full. If it's a metal tank, if you have a tank with just some metal fittings like at the bottom edge of it,