The video shows a group of fish swimming in an aquarium. The fish are of different sizes and colors, and they are swimming around the tank, which is filled with water and rocks. The fish are moving around the tank, and some are swimming near the surface while others are near the bottom. The aquarium is well-lit, and the water is clear, allowing for a good view of the fish and their surroundings. The fish appear to be healthy and active, and they are interacting with each other in a natural way.