Here is what I did:
About 2 cups of frozen watermelon balls
about 3/4 cups watermelon juice (as I scooped the balls, I drained the juice into a cup.)
1 scoop Splenda
1/2 cup homemade greek yogurt
a few splashes Amaretto sugar free syrup (I'll use less next time)
a few sprinkles lemon-flavor jello
Gracie and I are enjoying them now.