416bigbore
Ruffus and Big Boy
IMO, Without the aid of a chemical like chlorine and the risk of permanently hurting your fowl. I don't think you can kill Algae, only slow it down until you properly clean the container.
https://www.backyardchickens.com/threads/algae-and-the-pink-stuff-in-my-ducks-water-dish.1407140/

https://www.backyardchickens.com/threads/algae-and-the-pink-stuff-in-my-ducks-water-dish.1407140/