RE: Plastic fittings for Water/Juice Bottles
I have found it nice to use a short piece of neoprene at the fuel dot, as the tygon does not like to let go of the barbed dot. Easily to replace when it wheres out.
Also, the Tygon will stay soft in the tank if you leave some gas in there.
Funny how all of these components for gas are really a pain I believe. Glow fuel is so less caustic on tubing and stoppers and such. Raw gas does play hell with your finish as well. Mainly the latest synth oils I believe.