The video shows a yellow fish with a large mouth and orange eyes swimming in an aquarium. The fish is seen eating a crab, which is lying on the sandy bottom of the tank. The fish approaches the crab, opens its mouth, and bites down on the crab, which appears to be dead. The fish then swallows the crab whole. The aquarium is well-lit, and the water is clear, allowing for a good view of the fish and its prey.