The Aquarium Bia-Balls have a structure of dense holes where live a lot of nitro-bacteria;Weight: 160. 4gPackage include: 18 x Bio-Balls Filtration
18 black bio-balls excellent for oxygenating your water and helping the gas exchange process
It features plastic construction with high performance stuffing
Great for any freshwater or saltwater fish tank or mini-reef aquarium.
These Fish Tank Filter are simply rinse and use.
Each ball size: 3 5cm(diameter)
