Polish !!! :-)
If it gets too bad i'll buff it up again or i may just laqlacquer it..
I'm surprised the drain cleaner didn't just eat the light.
It probably won't go dull quickly - aluminium forms an oxide layer essentially instantly in contact with air. If you get aluminium to burn you will rapidly realise that it is very, very chemically reactive. It is far more reactive than magnesium - but it forms an oxide layer essentially instantaneously that stops it burning spontaneously in air. Look up thermite too see just how reactive aluminium is.
It'd probably be a good idea to head to Halfords and get some clear lacquer though. Wash the light down with meths or similar first - then let it dry and spray it.
It seems that it's not made entirely from aluminium but an aluminium alloy as the body was a lot harder to polish and also seems too heavy for pure aluminium.
A few new "slightly better" pics !!!
