I boat in an area where non-ethanol fuel is not available. I have been using Valvtect XP+ Gasoline Treatment at every fill-up and during five months of winter layup for each of the past three years. Put another way, that’s 1,700 gallons of gasoline I have treated without suffering any ill effects of phase separation, octane loss or a gunked-up fuel system. Simply use a ratio of 1 ounce of treatment to 10 gallons of gasoline. It’s available in 4-, 16- and 32-ounce bottles. $5.99 to $21.99; defender.com
