Almarz wrote:
[...]
modern gasses. You may find something interesting, and remember that
you're filling portable bottles, not system bottles. When was the
last time it was freezing inside your cabin?

Careful about that one. As any gas is released from the tank it expands and
will cool down significantly. That's why you get frost on e.g. propane
tanks. And there have been fatality diving accidents when regulators froze
in above-freezing temperatures because of the expanding gas.

jue