The video shows a close-up of a blue and yellow fish swimming in a tank. The fish has a blue body with a yellow tail and a yellow stripe on its side. It swims near a rock and then moves away. The tank also contains other fish, including a clownfish and a yellow fish with black stripes. The blue and yellow fish is the main focus of the video, and it is seen swimming in different directions. The tank appears to be well-maintained, with clear water and a variety of fish.