Add the sugar to a half gallon glass jar, if using.
Add the coconut water to the jar.
Stir thoroughly to dissolve the sugar.
Add the hydrated kefir grains to the sweetened coconut water.
Cover the jar with a plastic lid, cloth cover secured with a rubber band, or fermentation cap.
Let sit in a warm place (70-78°F) for 24-48 hours to ferment.
If the sugar is omitted, taste it after 24 hours. If using the sugar, allow for 48 hours. It should taste like tangy coconut water.
Strain out the kefir grains with a cheesecloth or non-metal strainer. The grains can be used to immediately start another batch of water or coconut water kefir.
Once the grains are removed, you may add flavors for a second fermentation or drink plain. See notes for a link to flavor options and instructions for a second ferment.
Store the finished product in the refrigerator and enjoy chilled!
Notes
White sugar and organic evaporated cane juice crystals are the best choices with the coconut water.You can use frozen coconut water or coconut water from tetrapaks (cartons). Check out this post for details about flavoring water kefir in a second ferment.