Prepare the Ginger Bug (5-7 days in advance): In a clean quart-sized jar, combine 2 tablespoons grated fresh ginger, 2 tablespoons granulated sugar, and 1 cup filtered water. Stir well. Cover the jar with a breathable cloth (like cheesecloth) secured with a rubber band, and let it sit at room temperature. Each day for 5-7 days, "feed" your bug by stirring in 1 tablespoon grated ginger and 1 tablespoon granulated sugar. It's ready when it smells tangy and has a visible layer of foam or bubbles on top.

Make the Ginger Soda Base: In a large pitcher or bowl, combine 4 cups of filtered water with 1/2 cup granulated sugar. Stir until the sugar is completely dissolved. Adjust sugar to your preference.

Combine and Bottle: Strain 1/2 cup of the active ginger bug liquid into the sugar water mixture. Discard the ginger solids or compost them. Pour the mixture into clean, food-grade glass bottles with swing tops or secure lids, leaving at least 1-2 inches of headspace to prevent explosions.

Second Fermentation (Carbonation): Seal the bottles tightly. Place them at room temperature, away from direct sunlight, for 2-5 days. This is the second fermentation, where the yeast in the ginger bug consumes the sugar and produces carbon dioxide, creating fizz.

Burp the Bottles Daily: It's crucial to "burp" your bottles daily (or even twice a day if your home is warm) by opening the caps briefly to release excess pressure. This prevents bottles from exploding.

Chill and Enjoy: Once the soda reaches your desired level of fizziness (you can carefully taste a small amount daily), transfer the bottles to the refrigerator. Chilling slows down the fermentation process significantly. Serve cold and enjoy your homemade, gut-friendly probiotic ginger soda!