The video shows a fish swimming in an aquarium. The fish is yellow in color and has a long tail. The aquarium is well-lit, and the water is clear. The fish is seen swimming around the tank, exploring its surroundings. The aquarium appears to be well-maintained, with no visible algae or debris. The fish seems healthy and active, moving smoothly through the water. The video does not show any other fish or objects in the tank, focusing solely on the yellow fish.