I just wanted to share some success!
On a lark I grabbed a 2 at jug of 100% grape juice at the store... When I got home I put it in a big, open plastic jug, added a half cup of sugar and 1 cup of my lovely ginger bug.
After aerating the heck out if it twice a day for three days I strained and bottled it back in its original jug. Just 8 HOURS later it was about to explode!
I let some of the carbonation out and tested it... BAM! Just perfect tartness and fizz that won't stop!
Try this out!