welcome aboard
sno-bowl toilet cleaner from the dollar store for cleaning mineral buildup
if you plan on polishing, you will need to first clean, then wet-sand, then go thru multiple compounds to machine polish the aluminum logs, then you need to apply a sealant like sharkhide every few months in between re-buffing.
Im my mind, hit it with a brush and toilet cleaner to remove minerals, wash with simple green, then go boating.