The video shows various fish swimming in an aquarium. In the foreground, a vibrant blue tang with a yellow tail, also known as Dory, is visible. Other fish species, including a white and yellow fish and several smaller dark fish, are swimming around a rocky coral reef environment. The water is a deep blue, and there are various aquatic plants and structures providing hiding spots for the fish. The camera captures the fish swimming leisurely, showcasing the diverse marine life in the aquarium.