In the video, there are several fish swimming in an aquarium. The fish are of different sizes and colors, including shades of brown, orange, and gray. They are swimming around in the water, which appears to be clear and clean. The aquarium is decorated with green plants, which provide a natural habitat for the fish. The fish are moving in different directions, some swimming near the surface while others are closer to the bottom of the tank. The lighting in the aquarium is bright, highlighting the colors of the fish and the greenery of the plants.