Aquarium tubing I believe is vinyl? That will not be fuel compatible.
From here:.. Tubing: Teflon Tubing, Silicone Tubing, Poly Tubing, Vinyl Tubing
Vinyl tubing is a clear flexible tubing providing an economical means of fluid transfer in a variety of applications. Intermittent exposure to hydrocarbons, such as gasoline, kerosene, diesel fuel, etc. will cause premature hardening and failure of the tubing.
This has proven to be my favorite stuff so far . Tygon Fuel Grade Tubing, F-4040-A Series. Fuel Grade Poly Vinyl Chloride (PVC) Clear Tubing.