carrying extra fuel...i read this on another site i participate on-"i strap down a few 5 gallon jugs on my swim platform" "when i'm offshore,i pour them in the tank"...
this may offend a few of you-sorry in advance...
this is the dumbest thing i've read,this is advertising you're stupid,and asking for trouble...another "genius" suggested he uses "an old fuel pump,scavenged from an old efi motor,mounted on a piece of plywood"...
i realize necisity is the mother of invention,but...this is pushing the boundries of common sense,yes ?
bladder tanks are equally as bad,ever see one marked "coast guard aproved " the name of the game is to be as safe as possible,yes ? you're responsible for your crew-remember that...if you need to have more fuel,and you've got an outboard powered boat,it's a simple fix,bring along a portable tank,plug it in to the fuel seperator and off you go,run it till it's dry,then move it forward out of the way...
inboards and sterndrives are a little different,you will need an aux tank installed...look for room,you WILL find it,this is the safest way to do it...if you can't do that,then get a nother boat,one with more fuel capacity...
DO NOT TRANSFER FUEL AT SEA WITH FUNNELS AND 5G CANS...

Jimmy,
Years ago I was one of those dummies. We were desperate to get to the canyons and always wanted to have extra fuel to be 'safe.' I did it about five times and learned that going to the NJ canyons on a 24' boat with marginal fuel capacity was just not worth the effort. We would run out till we burned about 25 gallons, dump the five containers in the tank, troll all afternoon, anchor or drift overnight, troll all morning and run home. Never actually needed the extra fuel, but came very close once when the seas were a little nasty.

I now have a larger boat with ample fuel capacity. Looking back, buying a 25 gallon plastic deck tank for about $100 would have been a much smarter move. No mess, no gasoline smell on your hands (and bait, lures, etc) and much safer.

I don't always agree with Jawz, but he is absolutely correct with his statements above. Another idea to consider is to go on an open boat trip with one of the charter captains on this site. Many captains go offshore regularly and have room for one more or even a couple of guys.