In the video, a group of people, including two children, are seen observing a large fish in an aquarium. The fish is swimming around in the water, surrounded by smaller fish. The children are standing in front of the aquarium, looking at the fish with interest. The aquarium is well-lit, and the water is clear, allowing for a good view of the fish. The children seem to be fascinated by the sight of the large fish, and their attention is focused on it. The video captures the moment from a side angle, providing a clear view of the fish and the children.