大象传媒

After a night's grazing on land, hippos return to a pool to rest during the heat of the day. Soon after arriving in the pool, each hippo is trailed by a small shoal of barbel waiting for their breakfast - hippo dung. It's not just the dung these fish feed upon, they also pick off small ticks and parasites that live on the hippos' skin. When the hippos reach one particular spot in the pool, they stand still and enjoy the clean up. And there's still a treat to come. After the hors d'oeuvre of dung and skin parasites, the hippos open their jaws and the barbel swim right in for a spot of dental hygiene!