Aluminum parts?

I am wanting to get these aluminum valve covers, and i got a bare aluminum street dominator intake and the aluminum water pump. I dont want to paint them because i like the look of the aluminum, but what can you do to keep the stuff clean where it wont get that whitish oxidation/corrosion or whatever that is that gets on aluminum over time..?
Big Block Plymouth Mopar Chrysler Dodge FABRICATED Aluminum Valve Covers 383 440 | eBay