CLR will work but I dunno about aluminum. Vinegar too, probably better for the Al. Home Depot used to sell a calcium/rust remover that was great. A lot stronger than CLR, but it was designated hazardous material and they don’t carry it any more. I looked at the label and the primary ingrediant was HCl acid. I bet if you went to a plumbing supply house they would have something similar to that. Again, not sure about the Al.
Oh and with the vinegar or CLR, the warmer the better, but not hot.