Slice watermelon into small pieces and discard rind.
Place into a large pot with water. Heat the liquid at medium-high heat until the base melts into a liquid.
Use a strainer to discard remaining watermelon pieces.
Measure 1 gallon/16 cups of watermelon juice and pour into your container.
Open your Brewsy bag and pour the contents in. Seal your juice again and shake well.
Apply airlock, add water to 'fill line', and leave in a dark and warm place (75-77 degree F) for three days. Cover with towel if necessary for darkness and/or keeping warm. Save the juice cap!
Using the values from the sweetness calculator, pour out your juice, add sugar, seal the juice again, and shake to dissolved (it's okay if it all doesn't dissolve) .
Open your Brewsy bag and pour the contents in. Seal your juice again and shake well.
Replace your juice cap with your airlock (see video here), add water to 'fill line', and leave in a dark and warm place (75-77 degree F) for three days. Cover with towel if necessary for darkness and/or keeping warm. Save the juice cap!
Final Instructions (universal for both methods)
After 3 days, move to fridge for 48 hours. Optional: remove the airlock and replace with the original cap, but *not* tightened onto the juice container. Instead, leave it loosely on top.
After 48+ hours in the fridge, your yeast will have fallen to the bottom of your container. Optionally, you can now carefully pour your wine off of the sediment into a secondary container for bottling. You may find that sediment will build up again, and your wine might need to be poured off ('racked') once more. NOTE: this sediment is completely safe to drink if accidentally consumed.
Enjoy! Your wine will continue to improve with age.