In the video, a person is seen cleaning the glass of an aquarium using a small brush. The aquarium is filled with water and has various fish swimming around. The person is wearing a blue glove and is using the brush to clean the glass thoroughly. The fish in the aquarium are of different sizes and colors, and they are swimming around the tank. The person is focused on cleaning the glass, and the fish seem to be undisturbed by the cleaning process. The aquarium appears to be well-maintained, with clear water and healthy-looking fish.