The video shows a fish swimming in a green water tank. The fish is brown and has a long tail. It is swimming around the tank, and its movements cause ripples and bubbles in the water. The fish is the only visible creature in the tank, and it appears to be healthy and active. The tank is well-lit, and the water is clear, allowing for a good view of the fish and its surroundings. The fish seems to be exploring its environment, occasionally coming close to the camera before swimming away.