I'm told the 12G remote tank can support 48 hours of run time (which is a lot BTW). So, no, I never had a need to carry extra fuel. I top off my tank with a Tempo 12G (square shaped) plastic tank and a siphon.
I place the Tempo on top of the aft fish box hatch, open the diesel fill cap, and the siphon easily fills the tank.
You could do this technique as well. If the Tempo (or equivalent) sat on a wet towel on your fish deck, it shouldn't move at all. The nice thing about a square shaped tank is it doesn't (can't) want to naturally tip over. Hope this helps.
