The video shows a fish swimming in an aquarium. The aquarium is decorated with rocks and has a blue light that illuminates the scene. The fish is small and dark-colored, and it swims around the rocks and the sandy bottom of the aquarium. The water is clear, and the fish moves smoothly through it. The rocks are of various sizes and shapes, and they are placed in different areas of the aquarium. The sandy bottom is light-colored and covers the entire bottom of the aquarium. The blue light creates a calming and serene atmosphere in the aquarium.