A pomelo is closely related to a grapefruit. It has the sweetness of an orange and the tartness of a lemon. Pomelo's health benefits are many and include the ability to boost the immune system, lower blood pressure, reduce cramping, reduce signs of premature aging, protect heart health, aid in weight loss, and boost oral and dental health. If you can't find pomelos, you can substitute grapefruit instead.
Make sure you use good bottles made for brewing.