100% brand new and high quality Aquarium Fish Tank Filter Bio Balls Bio-Balls. Each ball features plastic construction and high performance padding. < p>Black Bio-Balls have a dense hole structure where lots of nitro-bacteria live. 100pcs filter bio-balls excellent for oxygenating your water and helping the gas exchange process.< /p> Ideal for any freshwater or saltwater aquarium or mini-reef aquarium.
