just so you know Hockey4mnhs, after you make a post, you can hit the "edit" butten, and make changes/corrections if you feel like something you wrote wasn't correct.
Peakster, I woudl imagine it's not only temperature, but various blends as well. When i was changing fuel pumps i had about 80 lbs of fuel in my tank, but then again, it was heavier than gasoline :-P
Also, this is an intersting idea, but i would defintly NOT recommend it to people who live in below freezing climates, Something about frost and ice building up in the fuel tank (n) very poopy thing to deal with in winter.