We are try re having so much fun using our Ninja thirsti machine to customize our drinks to our liking.  This drink system is very easy to use and is nice to be able to choose different fizz strengths and flavors.  It comes with a removable water reservoir that holds 48 oz of water and a CO2 canister that is used for the carbonation.   Best of all, the taste of the flavored carbonate water is so refreshing.  I can’t wait to try all the flavors.  My kids are all distance runners and love coming home from races and making themselves a cool drink!   We love the thirsti system!