Filter Foam Insert Exo Terra Bio-Foam for AC20 aquarium filter (replacement sponge)

Exo Terra Bio-Foam is a replacement foam insert designed for the AC20 aquarium filter. It functions as a combined mechanical and biological medium: mechanically trapping suspended debris and particulates while providing porous surface area for colonisation by nitrifying bacteria. The foam helps maintain water clarity and contributes to stable biological filtration in small to medium aquaria when used as part of routine filter maintenance and cartridge replacement.

Advantages

The foam offers open-cell porosity that captures waste particles without significantly restricting flow, supporting both mechanical and biological filtration in a single component. Its resilient structure is suitable for repeated rinsing during regular maintenance and retains shape within the filter housing. The neutral material does not introduce dyes or additives that could affect water chemistry when used according to maintenance guidelines.

Suitable for

• Replacement media for AC20 aquarium filter units
• Mechanical removal of suspended debris in small to medium tanks
• Biological support by providing surface for beneficial bacteria growth
• Routine cartridge replacement during scheduled filter maintenance

Key specifications

• Material: open-cell foam designed for aquarium use
• Filtration type: combined mechanical and biological
• Fitment: shaped to fit the AC20 filter cartridge slot
• Maintenance: washable and reusable for multiple cleaning cycles

How to use

Turn off and unplug the filter before performing maintenance. Remove the existing cartridge or foam insert from the AC20 housing and replace it with the Bio-Foam insert, ensuring correct orientation and secure seating. Rinse the foam gently in tank water during routine maintenance to remove trapped debris while preserving beneficial bacteria; avoid using tap water with strong chlorination that could harm bacterial colonies. Reassemble the filter and restart according to the filter manufacturer’s instructions.

Usage recommendations

Recommend inspecting the foam at regular intervals and replacing it as part of scheduled maintenance or when excessive wear or irreversible fouling is observed. For optimal biological stability, perform partial rinses in aquarium water rather than full replacements each cycle, and combine with appropriate chemical or mechanical media as needed for heavy bioloads.