Place Jell-O in a mixing bowl add 3 cups of boiling water, stir to dissolve Jell-O. Place the two and one half cups of cold water in Jell-O and blend thoroughly. Pour one cup of gelatin in small bowl and set aside and do not chill. Place Jell-O in a serving dish or 13" x 9" pan.
Chill Jell-O until soft set. When Jell-O is soft set remove from refrigerator. Place fruit cocktail that has been drained, on top of Jell-O. Sprinkle coconut on top of fruit cocktail place marshmallows on top of all and arrange evenly. Press all very lightly with a spoon. Finally pour the reserved liquid Jell-O mixture on top of marshmallows. Place Jell-O back into the refrigerator until the salad is completely set.