The video shows a yellow seahorse swimming in a tank. The seahorse is seen moving around the tank, and at one point, it is seen hanging onto a plant. The tank appears to be well-lit, and the seahorse's movements are smooth and graceful. The plant has long, thin leaves that sway gently in the water. The seahorse's body is curved, and its tail is long and thin. The color of the seahorse is a bright yellow, and it stands out against the darker background of the tank.