Why is Chinese grass carp used to control aquatic vegetation?

The Chinese grass carp (Ctenopharyngodon idella) is used to control aquatic vegetation because it is a herbivorous fish that consumes noxious aquatic plants.1

In the 1960s, the U.S. Fish and Wildlife Service imported these grass carp to evaluate them as a biological alternative to chemical herbicides and mechanical methods for managing weed growth in ponds, fish farms, and small lakes. While they effectively target specific aquatic vegetation, their introduction has led to concerns regarding their status as an invasive species in non-native waters, as they can significantly reduce the supply of aquatic plants and potentially disrupt local ecological dynamics if they escape into larger river systems.21