The video shows a fish swimming in a tank. The fish is dark in color and has a long tail. The tank is made of glass and has a metal grid on the top. The fish is swimming around the tank, and its movements are smooth and graceful. The water in the tank is clear, and the lighting is bright, making the fish's movements easy to see. There are no other fish or objects in the tank, and the background is blurred, but it appears to be a room with furniture.