Prepare the Base: Pour a layer of salt into the bottom of the clear bottle until it covers the base.
Add Warm Water: Fill the bottle with warm water up to a quarter full.
Dissolve the Salt: Mix the water until the salt has completely dissolved, then allow the water to cool.
Add Cool Water: Carefully pour in cool water until the bottle is three-quarters full.
Layer the Oil: Pour about 1 cm of oil into the bottle on top of the water.
Prepare the Colour Mixture: In a small bowl, combine 1 tablespoon of oil with 7 drops of food colouring. Gently stir the mixture until the food colour breaks into smaller spots.
Create the Fireworks: Slowly pour the coloured oil mixture into the bottle and watch as the food colouring drops down through the water, creating a beautiful "fireworks" effect!
