Watermelons will vary in sweetness. This recipe is on the lower end of added sugar, so if you have a nice, sweet watermelon, you won’t over sugar the aqua fresca. But if your watermelon is the best, you might want to add more sugar and/or lime juice. Watermelon aqua frescas are also perfect to use up watermelon that doesn't have the best texture, but have good flavor. It’s best served nice and chilled, so make sure to chill completely before serving.
Combine the watermelon cubes, lime juice, sugar, and water in a blender.
Blend until smooth. Taste and adjust flavor to personal preference.
(Optional) Strain the juice and discard the remaining pulp.
Cover and chill completely. Keep chilled until ready to serve. It's best to make sure the drink is fully chilled so that the ice doesn't melt too fast and water down the drink.