Drain oranges and pineapple, reserving juices. Set oranges and pineapple aside. Add water to juices to measure 2 cups. Place in a saucepan and bring to a boil; pour over gelatin in a bowl. Stir until gelatin is completely dissolved. Stir in seven up or juice.
Chill until partially set (watch carefully). Fold in oranges, pineapple, blueberries, mini marshmallows and coconut. Pour into a 6-cup mold. Chill until firm.