I use Sta-bil in my Jerry cans - I have one for 25:1 mix and 1 straight unleaded petrol. I only use bp ultimate for no other reason that I�m pretty confident it has no ethanol according to the data sheets. Sta-bil is supposed to keep fuel from going off or gunning up for up to 2 years. I�ve found it very good. There is also a marine version which is supposed to remove water from fuel and prevent ethanol damage (from the website)
