Filter bio ball MARINA Aqua Natura, replacement cartridge, Ø 42 mm, PP

MARINA Aqua Natura bio ball is a replacement filter cartridge made from polypropylene with a diameter of 42 mm. The porous spherical shape offers increased surface area for colonisation by nitrifying bacteria, supporting biological filtration in freshwater aquarium systems. This cartridge is intended for routine replacement in compatible small filters to maintain stable water parameters and reduce organic load.

Advantages

The polypropylene construction is resistant to degradation in aquarium water and provides a consistent porous structure that encourages beneficial bacterial growth. Its compact 42 mm diameter makes it suitable for small filter housings while allowing efficient water flow around the media. As a dedicated biological media, it helps stabilise ammonia and nitrite levels when used as part of a complete filtration routine.

Suitable for (tasks / use cases)

• Biological filtration in small to medium freshwater aquariums
• Replacement cartridge for compatible external or internal filter units
• Supporting nitrification and reducing toxic nitrogen compounds
• Routine maintenance and periodic media replacement

When it may not be suitable

This bio ball is designed specifically for biological filtration and does not provide mechanical or chemical filtration on its own; it should be used alongside mechanical sponges or chemical media when particulate removal or toxin adsorption is required. It may not fit larger filter systems or housings that require a different cartridge size or shape.

Key specifications

• Material: polypropylene (PP)
• Shape: porous spherical bio ball
• Diameter: 42 mm
• Intended function: biological filter media for aquarium use

How to use

Place the bio ball inside the filter chamber or designated cartridge slot where biological media are recommended. Ensure water flow passes over and through the porous surface to maximise bacterial colonisation. Replace the cartridge according to the aquarium’s maintenance schedule or when water quality measurements indicate reduced biological activity. Rinse only with aquarium water if temporary cleaning is necessary to avoid removing beneficial bacteria.

What to consider before purchase

• Confirm the 42 mm diameter and spherical shape fit your filter housing or cartridge holder
• Understand that this item provides biological filtration only and may need to be paired with mechanical or chemical media
• Check compatibility with freshwater systems and the specific filter model before ordering

Usage recommendations

Introduce the bio ball into the filter as part of a layered media approach: mechanical filtration first to remove solids, followed by biological media like this bio ball. Allow a stabilization period after installation for beneficial bacteria to establish before relying on it for full nitrification; monitor ammonia and nitrite levels during this period.