General question for everyone to have a go at. What I am giving serious thought to is buying a used vessel (size measured in barrels not gallons) so yes very big. I intend to insulate very well with foam if I can't buy one already insulated. They are available used from a wide variety of industries breweries, wineries, nat gas, oil etc....some rated to insane pressures at temps exceeding 400 °F, some pre insulated with high temp foam, others at atmospheric pressures with no insulation....anyhow I guess my question is how much is too much??? Space is not a consideration. I will avoid the 50,000 barrel units as the freight would probably be insane. Are there any issues on size of storage Re: thermodynamics (for all you math majors) or other issues that I should consider???? As always your thoughts & input are more than welcome (helps me learn).