The video shows a close-up of a crab inside an aquarium. The crab is seen climbing onto a piece of cloth that is hanging from the top of the aquarium. The crab then climbs onto a piece of wood that is also hanging from the top of the aquarium. The crab moves around the aquarium, exploring its surroundings. The aquarium is well-lit, and the water is clear. The crab is dark in color, and its movements are slow and deliberate. The video does not contain any other creatures or objects.