The video shows a large group of fish swimming in a blue-lit aquarium. The fish are mostly silver in color with some darker spots. They are swimming in a coordinated manner, creating a mesmerizing effect. The background is a deep blue color, and the fish move in and out of the frame. The video also includes several jellyfish floating in the water, their translucent bodies gently pulsating as they move. The jellyfish are of various sizes and are also illuminated by the blue light.