Fluval Bio FX Biological Media 5ltr Box

• High surface area – 2,250 m² per litre, or roughly 11,250 m² across the full 5 L pack, for a large ceramic ring media.
• Deep pore structure – interconnected micro-tunnels increase dwell time so bacteria have longer contact with passing water.
• Two nugget sizes – mixed grades pack more tightly without choking flow through the basket.
• Zip-mesh bag included – lift the whole 5 L charge out for rinsing without handling loose media.
• Inert ceramic – won't alter pH or leach into the water column.

Fluval doesn't restrict Bio-FX to one model – it's sold as media for any canister filter or sump, and appears on Fluval's own site alongside the 07 Series (107/207/307/407) and the FX4/FX6 canisters. If your filter has a basket stage sized for loose media, this will fit; the mesh bag lets you portion it to whatever basket volume you have spare, so a single 5 L box will often span more than one filter's final stage over its life.

Rinse monthly in removed aquarium water, never tap water – chlorine and chloramine kill the bacteria colony living in the media. Replace roughly a third to a half of the charge every six months rather than the whole basket at once, so the colony re-establishes without triggering a mini-cycle.

Suitable for any freshwater or saltwater system running a canister filter or sump with a dedicated biological stage. Not a substitute for mechanical or chemical media – it doesn't remove floating debris or discolouration, so it belongs after your mechanical and carbon or chemical stages, not before them.

Covered by Fluval's standard consumer guarantee against manufacturing defects, in addition to your rights under Australian Consumer Law. Standard freight class, no special handling required.

How much do I need for a standard bioload?

For an averagely stocked tank, filling one basket layer with Bio-FX is typically enough. Heavily stocked or messy setups benefit from devoting a full basket to biological media.

Can I mix Bio-FX with other Fluval ceramic media?

Yes. It's designed to sit alongside BioMax or other porous ceramic media in the same basket – the two nugget sizes already give it some size variation on their own.

Does it need to be cycled before use?

Like any new biological media, it starts without a bacteria colony. Add it to an established, already-cycled filter alongside existing media so bacteria can colonise it, or dose a bacterial starter at setup.