I did the standard fuel test a couple of weeks ago where you put gasoline in a test tube with a little water, measure levels and then come back a few hours later and measure again. Amazing how much water ethanol can absorb even at 2% of the total by volume. The bad thing is that the water condenses back out some time later in storage leading to all kinds of problems. This is called phase separation and there is no practical way to avoid it.
Yep, I’m using Startron as a preventive. Works well so far but waht a PIA for older fiberglass gas tanks this alcohol crap is.
http://mystarbrite.com/startron/