Algaecide

Algaecide or algicide is a biocide used for killing and preventing the growth of algae. Algaecide or algicide is a biocide used for killing and preventing the growth of algae. Barley straw, in England, is placed in mesh bags and floated in fish ponds or water gardens to help reduce algal growth without harming pond plants and animals. Barley straw has not been approved by the United States Environmental Protection Agency (EPA) for use as a pesticide and its effectiveness as an algaecide in ponds has produced mixed results during university testing in the United States and England.