CrystalClear BioClarifier naturally clears the water, removes odors, and breaks down suspended dead debris and decaying leaves with billions of bacteria colonies and added enzymes. The result is a cleaner pond, happier fish, improved dissolved oxygen levels, and reduced ammonia levels. CrystalClear BioClarifier comes in easy-to-use water-soluble packets and can be used in ponds, fountains, bubblers, and disappearing waterfall features. Use when water temperatures are above 50°F.