> 6 cups cold water, divided
> 3/4 cup sugar
> 1 large red grapefruit
> 3- 4 lemons
> 2- 3 limes
> 2 (6 oz) containers fresh raspberries
In a medium pot, combine 2 cups water and sugar. Heat on high, until sugar dissolves, stirring occasionally. Remove from heat and let cool.
Meanwhile, squeeze the grapefruit to get ¾ cup juice. Squeeze the lemons to get 1 cup juice. Squeeze the limes to get ¼ cup juice. Add all juices to a pitcher.
In a blender, purée the raspberries until smooth. Strain through a fine-mesh sieve into the pitcher with citrus juices, pushing on solids to extract all the juice. Discard solids.
To pitcher with citrus juices, add sugar syrup and remaining 4 cups cold water. Stir to combine. Refrigerate until cold. Serve over ice. Garnish with additional lemons, limes, or raspberries, if desired.