Hi Paul,
Welcome to the forum.
With regard to protecting the aluminium, I don't. I've even stopped polishing mine. It hasn't been polished now in 2 years and it still looks great, although the possibly not quite as shiny as it once was, but I like that.
The aluminium is really high quality and doesn't tarnish at all. I just use a vinegar type window cleaner to get dead flies and finger prints off. However, bear in mind that mine is polished and yours is brushed. The brushed finish is perfectly designed to hold onto every atom of dirt and every smear of grease, so be prepared for many hours of cleaning.
Paul