Watch as the jellyfish glide hypnotically through the coloured lights liquid filled light with three jelly fish that swim about inside fill the tank with water and then flick the switch to illuminate the colourful leds and start the water current that makes the jellyfish bob up and down as the jellyfish swim they change direction as their tendrils flicker creating a calming a surprisingly realistic effect optional mains power cable not included requires 3 x aa batteries 23cm tall