Bioballen

Bioballen, also known as bio balls, are a type of biological filtration media used in aquariums and pond filters. They consist of small plastic spheres with a porous or hollow interior designed to provide a large surface area for beneficial bacteria to colonize. The goal is to create an efficient home for nitrifying bacteria that help break down toxic waste produced by fish and uneaten food.

Bioballen are typically made from lightweight plastics such as polyethylene or polypropylene. They may be hollow and feature irregular or grooved surfaces to maximize surface area and maintain water flow through the media. Their porous construction allows water to contact a large area of bacterial habitat while remaining relatively open to avoid complete clogging.

In operation, bio balls support biological filtration by hosting nitrifying bacteria, which convert ammonia to nitrite and then nitrate. This process reduces the concentration of toxic compounds in the water and is commonly complemented by mechanical and chemical filtration steps. Bioballen are often used in various filter configurations, including canister filters and trickle or waterfall-style filters, and can be combined with other media like sponges or ceramic rings.

Maintenance involves periodic rinsing of the media in old aquarium water to remove accumulated waste and prevent detritus buildup. Tap water should be avoided, as it can kill beneficial bacteria. Over time bioballen can become compacted or clogged, reducing flow and aeration, and may require cleaning or replacement.

Advantages of bioballen include simple design, low cost, and high surface area for bacterial growth. Disadvantages can include clogging if filtration flow is restricted and reduced efficiency compared with newer media in some setups. They are typically used as part of a layered filtration system rather than as the sole filtration medium.