Jungle Pond Block Single An easy, effective way to control and prevent the growth of algae in your pond. Not recommended for use in ponds with live plants.4-pack: Treats up to 1000 Gallons (3785.5 L). Product Type: Pond Medication for either freshwater or saltwater aquariumsKeywords: Additives / Planted Aquarium / Reef Aquarium / Tools / All Collections