How to protect from Ethanol Phase Separation in Bertram Fiberglass Gas Tanks with E-10 Gasoline?

You have 2 choices really. You can fill it up and treat it or you should empty it entirely and run your engine out of gas also. If you leave it any other way you invite trouble. Ethanol will pull moisture out of the air and into the tank also giving you troubles. We have had ethanol for a few years in the northeast now so if you have not had trouble yet you should be fine leaving it full and treating it. Good luck.  more