Help make your tank more hospitable for underwater buddies with TL Reefs PHA Aquarium Biopellets， Nitrate & Phosphate Reducer. Made of 100% pure PHA biopellets， it naturally reduces phosphate and nitrate levels in your aquarium as the pellets provide a food source for bacteria that consume nitrate and phosphate. These pellets are uniform in size with a round shape for smooth fluidization with minimal floating or clumping. It also removes bacteria through several methods， including protein skimmer and consumption by tank inhabitants. TL Reefs PHA Aquarium Biopellets， Nitrate & Phosphate Reducer is safe for all fish and corals and works in all aquariums， filter bags， freshwater and saltwater.