Add the juice of 6 lemons, sugar, and whey to a half gallon Fido jar.
Add a few cups of filtered water and stir until the sugar is dissolved.
Add more water until the jar is filled to within an inch or two at the top. It’s important to leave some space in the jar.
Close the jar and cover it with a dishtowel and leave on your countertop for two days to ferment.
If you prefer a more tangy lemonade, you may leave the lemonade to ferment for a third day.
The sugar feeds the good bacteria as it ferments and the beverage becomes less sweet each day that you allow it to ferment. We find that two days is just perfect.
Notes
*Drained from plain yogurt, kefir, or leftover from cheese making.