Bring the 1 cup water to a boil over medium-high heat, and then stir in the sugar until it dissolves. Pour the sugar water into a quart-sized mason jar, and then pour in 3 cold water. Allow the sugar water to cool to room temperature.
Spoon the water kefir grains into the room temperature sugar water. Drop in the fig and lime. Let it culture at least 24 hours and up to 72 hours.
Strain the kefir through a nonreactive strainer into a pitcher. Discard the spent lime and fig, but reserve the water kefir grains.
Store the reserved kefir grains in sugar water in the fridge up to 2 weeks.
Serve the kefir right away, or continue with the secondary fermentation below.
For the secondary fermentation, pour 1 cup fruit juice into the kefir. And then pour the flavored kefir into flip-top bottles, filling them within ½ inch to 1 inch of their openings.
Seal the bottles, and set them on your countertop to ferment a further 18 to 24 hours, keeping in mind that warm temperatures will speed up the fermentation process while cool temperatures will slow it down. Transfer the bottles of water kefir to the fridge for 3 days to allow the bubbles to set.
Open carefully over a sink, as the liquid in the bottle is under pressure, and when you release the bottle's seal, the water kefir may fizz and foam.