Hagen AQUA CLEAR filter media cartridge 300/70 gravel insert for mechanical and biological filtration

Hagen AQUA CLEAR filter media cartridge 300/70 gravel insert for mechanical and biological filtration is a replacement media layer designed for Aqua Clear canister and hang-on filters. The insert contains gravel media that mechanically traps suspended debris while providing additional surface area for beneficial nitrifying bacteria. It is intended for use as a component in multi-stage filtration assemblies to enhance water clarity and support biological nitrogen cycling in freshwater or lightly planted aquariums.

Advantages

The gravel insert combines mechanical particle retention with porous surface area suitable for colonisation by bacteria, allowing simultaneous removal of particulates and support for biological processes. As a replaceable cartridge layer, it can be integrated into existing filter cartridges or media baskets, simplifying maintenance. The physical structure of the gravel promotes steady water flow through the media, helping maintain oxygen exchange and consistent filtration performance over time.

Suitable for (tasks / use cases)

• Mechanical removal of suspended particles and detritus in aquarium filtration
• Providing additional surface area for beneficial bacteria to support biological filtration
• Integration into multi-stage filtration setups in canister or hang-on Aqua Clear filters
• Use in freshwater and community aquariums where moderate mechanical and biological filtration is required

Key specifications

• Media type: gravel insert designed for mechanical and biological filtration
• Compatibility: designed for Aqua Clear 300/70 style filter cartridges and media compartments
• Function: traps particulate debris and offers surface area for bacterial colonisation
• Form factor: replaceable cartridge-layer insert suitable for multi-stage filter assemblies

How to use

Install the gravel insert as a layer inside the Aqua Clear filter cartridge or media basket according to the filter manufacturer’s assembly guidelines. Ensure water flow passes uniformly through the gravel layer to maximise mechanical trapping and contact with biological surfaces. Replace the insert at regular intervals or when excessive clogging reduces flow; rinse gently if short-term cleaning is needed, taking care not to remove established beneficial bacteria completely.

Usage recommendations

Inspect the insert periodically for accumulated debris and reduce replacement frequency by combining with finer mechanical media upstream. When performing maintenance, avoid aggressive scrubbing or use of chlorinated water to preserve bacterial colonies that support nitrification.