I've been working with the kefir water. It's been trial and error. What I'm wanting is kefir soda. What has been giving me problems is the "fizz". I finally got my grape soda to fizz really well tonight. Almost too well. LOL! So far I still have yet to get the ginger ale to fizz.
What I did was take the advice from several people. I'm letting my grains sit in the water for 48 hours, for now. I add the grape juice into the bottle, then the kefir water. I plug it, shake it, and let it sit 24 hours. I then vent it (an listen to see if it pops), then plug it, shake it, and let it sit another 24 hours. After that, I put it in the fridge.