The video shows a dolphin swimming in a large tank. The dolphin is seen swimming around the tank, and at one point, it opens its mouth wide. The water in the tank is clear, and the dolphin's movements are smooth and graceful. The dolphin's skin is a shiny gray color, and it has a long, pointed nose and a dorsal fin on its back. The tank appears to be well-maintained, with no visible debris or pollution. The lighting in the tank is bright, illuminating the dolphin and the surrounding water.