The video shows a group of fish swimming in an aquarium. The fish are of different colors and sizes, and they are swimming around a rock formation. The aquarium is decorated with sand and rocks, creating a natural environment for the fish. The fish are moving around the tank, exploring their surroundings and interacting with each other. The water is clear, and the lighting is bright, highlighting the vibrant colors of the fish. The video captures the peaceful and serene atmosphere of the aquarium, with the fish swimming calmly and gracefully.