Hi Al, Another means of filling a float tube is a small tank that Sears sells to carry in a vehicle to inflate tires, and whatever. It is about the size of a scuba tank, and requires nothing as most float tubes I have seen uses inner tubes.
Al, please be careful using a float tube, read my post, if you haven't already, in "Gear spoken here" One almost killed me. I gave mine away, and I haven't heard from the guy since. At any rate good luck. Just don't stumble walking backwards with fins on. I am going for an inflatable raft this year.