Try this beverage experiment:
Take one part legal grape juice and add an equal part sparkling water. Taste it. What do you think?
Be brave. Mix things.
Note that there is a significant difference between club soda and sparkling water. Club soda generally has some form of sodium and it I don’t think it works nearly as well as simple sparkling water due to it’s harsher taste. The sparkling water is essentially tasteless and lets the flavor of your juice shine through. Check the label and if it only lists carbonated water for the ingredients, than you are set.