500 x Bio Balls

Bio balls are a great form of biological filtration due to their incredibly high surface area to volume ratio.

Bio balls will grow a massive amount of beneficial bacteria on their surface, which, when pond water passes by, will remove harmful chemicals such as ammonia and nitrites from the water

This 30 litre netted bag is convenient to clean as you can pick up the whole mass to remove it from your filter box.

Weight 8 kg