How does a jellyfish lamp work?
The Jellyfish Mood Lamp, manufactured in Japan, is a novelty desk lamp or night light that holds water and several plastic jellyfish. The LED lights in the tank’s top rotate through several colors and allow the user to stop the rotation at any color that suits his mood.
If the fish fail to sink they may have small air bubbles on them, tapping the fish lightly will disperse the bubbles.