RE: Armoral in fuel?
I too am not aware of any commercial fuel blends that does not include an anti foaming package.
There is only one way to totally insure a complete absense of foam and that is using a bubbleless type tank that Arup and Jaka have already mentioned. They can be a tremendous advantage for certain problamatical airplanes and some types of flying.
As mentioned they are almost exclusively used world wide for pylon, The combat folks are rapidly learning of the advantages and they are very useful in controlline if constant fidlling with various uniflow schemes is not your cup of tea.
Although they are a combined suction/muffler pressure system as is the conventional tank they offer superior fuel delivery characteristics even to the point that in many cases they can be moved aft to the aircrafts CG (a big plus for a 3D type as well as some others) and still perform better than a conventional type.
The downside is of course they are around three times as expensive as the conventional tank but they can be hard mounted with no foam. Another downside is in crashs the bladder is normally ruptured.
John