Juice the lemons and strawberries and add the juice to a gallon-sized jar with a tight-fitting lid.Add the sugar and whey to the juice and mix well.
Fill the jar to the top with filtered water (tap water can disturb the live bacteria/cultures in the whey).
Cover tightly and let sit for two days.
After two days, it’s ready to drink!
Store in the refrigerator to stop the fermentation process.