I figure steel wool would work fine for the aluminum tubing,

I've read that it is *not* a good idea to use steel wool to clean up
aluminum, especially if it's going to be exposed to the weather.
There's a tendency for tiny bits of the steel to get caught in the
aluminum... it'll rust.

I'd suggest using a 3M (or generic equivalent) green abrasive
scrubbing pad. These pads are rough enough to remove oxidation from
copper PC board material, so I imagine they'll shine up aluminum just
as well, but they won't leave rustable material behind.

I know
how to test the traps, but I am wondering whether to use stainless
steel or galvanized hardware?

I believe that you can get some amount of electrolysis if galvanized
metal and aluminum are in contact, especially if the aluminum is not
well-anodized or if there is electrolyte around (e.g. if your area is
subject to salt spray). Some people in the boating trade claim "no
problem", others state that you should never use zinc-galvanized and
aluminum together.

Stainless-steel-and-aluminum seems to be the preferred combination.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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