Ammonia is the leading killer of tropical fish.? It is the result of decomposing waste and food in your aquarium. Combat this serious issue with our Ammonia Reducing Pads. They are specially infused with ammonia-absorbing particles that pull harmful ammonia from your aquarium or pond water. Like all our infused media pads,our long-lasting polyfiber material is up to twice as thick and is much more rigid than competing pads, enabling them to fit tighter, hold their shape longer, filter more effectively, and last longer.