Fishtank16

What is the difference between RO water and distilled water that is sold in supermarkets

I am fairly new to shrimp tanks and overwhelmed by all the products I see for sale. I purchased a package that contains cholla wood, Indian almond leaves, alder cones and Japanese tourmaline mineral balls. My question is in what combination should these be used or is it best to use only one product at a time. Guess I was in a hurry and thought they would come with some directions. i have 2 ten gallon tanks with red cherry shrimp