Hard water can leave behind a chalky white residue on your aluminum pots and pans. The scale most often appears after a pot has boiled dry. As the water evaporates, it leaves behind lime and other hard minerals that then adhere stubbornly to the inside of the pot. Standard scrubbing and washing won't break down or remove the scale. Mild acids break down the lime without damaging or scratching the aluminum. Thick buildup may take several cleaning treatments for complete removal, but light limescale wipes away quickly after just one treatment.
Fill the aluminum pot with 1 quart of water. Set the filled pot on the stovetop.
Mix 2 tbsp. cream of tartar with the water until it dissolves.
Heat the pot over medium-high heat until the water begins to boil. Boil for 10 minutes. The cream of tartar and heat work together to loosen the lime deposits.
Drain the water from the pot. Pour 2 to 3 tbsp. of white vinegar into the bottom of the pot.
Scrub the remaining limescale from the inside of the pot using a mildly abrasive cleaning pad and the white vinegar. The acid in the vinegar helps dissolve the remaining scale and mineral deposits. Rinse thoroughly with clear water after cleaning.