To clean Prills, leave them in their bag and rinse with running water, or… If they’re particularly stuck with minerals from sitting in hard water, place the bag in a bowl and cover it with vinegar. Let soak until the minerals loosen, then massage them gently and rinse thoroughly. If your Prills start growing green algae, please understand that this is natural, as they support life. Algae grow in all natural springs. If you want to get rid of the algae, rinse the Prills in hydrogen peroxide to bleach them, and keep your main Prill jug out of sunlight.