Combine the sugar and water in a nonreactive container. Transfer the syrup to the distillery container and let rest for two days at room temperature. Use or transfer to the fridge after two days and store there for up to a week.

To make the tart cherry soda, combine the cherry juice, simple syrup and lemon juice in a cocktail shaker filled with ice. Shake until well chilled—about 10 seconds.

Strain into an ice-filled rocks glass and top with the seltzer water.