Cut lemons and limes in half lengthwise. Use a spoon to remove the pulp from the inside. Place the lemon and lime halves in a muffin tin and set aside.
Bring water to a boil. Add gelatin packet and stir until it dissolves. Once dissolved, pour in a packet of Lemon Lime Hydration Multiplier Liquid IV.
Pour mixture into each hollowed-out lemon and lime half. Transfer to the fridge to set for at least 4 hours.
Once set, remove from the muffin tin, cut into slices and enjoy!