• Five-stage filtration — two mechanical stages (foam pad, then poly/foam pad), a chemical stage (activated carbon), and two biological stages (Bio-Screen pad and BIOMAX ceramic rings).
• Wet/dry trickle chamber — water splashes down through the biological stage rather than staying fully submerged, adding oxygen to the water and helping the bacteria colony living on the BIOMAX media.
• Patented refiltration design — as flow drops while media loads up, the filter routes some water back through the chamber a second time rather than just pushing it through faster.
• Clog indicator — a visual float rises as the foam pad loads up with debris, so you know when it needs a rinse rather than guessing.
• Quiet, low-wattage motor — 5 W continuous draw, designed to run day and night without a noticeable hum.

Fluval rates the C2 at 400 L/h on Australian 230–240 V/50 Hz power, measured with clean media and no restriction. Fluval does not publish a separate figure for flow with the media basket loaded — expect the rate to fall as the pads pick up debris, which is what the clog indicator is tracking. At the rated flow, here is roughly how many times the C2 turns over the water in tanks across its size range:

These are calculated from the manufacturer's rated flow, not measured on a loaded filter — actual turnover will sit below this once the foam pad has been running a few weeks, which is normal and expected.

The C2 clips onto the back or side of the aquarium and needs a rim or glass edge up to 2.5 cm (1") thick to hang from. It fits tanks up to 115 L. For anything larger, the Fluval C3 (up to 190 L) or C4 (up to 265 L) hang the same way but move more water — see the comparison below.

All three run at the same 5 W and share the same five-stage layout — the difference is chamber size and flow. Buy for your tank's actual water volume, not the tank's marketed size, and go up a size if you stock heavily.

• Filter housing and motor unit
• Poly/foam pad
• Activated carbon insert
• BIOMAX biological media
• Bio-Screen pad
• Intake tube and hang-on bracket

Suitable for freshwater and marine aquariums up to 115 L, including planted and lightly stocked community tanks. Not a substitute for a canister or sump on heavily stocked or large marine systems — at 400 L/h it's sized for small to medium tanks, not as the sole filtration on a large reef.

Rinse the foam pad in tank water (not tap water, which can harm the bacteria colony) whenever the clog indicator rises. Fluval's own guidance is to check the impeller and seal ring monthly and expect to replace individual media components roughly every 2–3 months, depending on bioload — heavily stocked tanks will need it sooner.

Mains-powered — always unplug before putting your hands in the water or removing the filter for cleaning. Rated to 230–240 V/50 Hz for the Australian market; do not run on an unearthed or damaged power lead.

• Fluval C2 Hang On Filter Poly/Foam Pad — the mechanical stage that wears out first
• Fluval C2 Hang On Filter Zeo-Carb — swap in for extra ammonia and odour control after a water change or medication course
• Fluval C2 Hang On Filter Impeller Assembly — keep a spare on hand; it's the one part that eventually needs replacing

Covered by Fluval's manufacturer warranty in addition to your rights under Australian Consumer Law. Standard freight — no special handling required.

Does the Fluval C2 work on saltwater tanks?

Yes — the housing and media are safe for both freshwater and marine use up to 115 L.

How loud is it?

Fluval markets the C series on quiet running, though it doesn't publish a decibel figure — most owners describe a soft trickle sound from the wet/dry chamber rather than a hum from the motor.

Can I use it on a bigger tank if I don't mind extra maintenance?

You can run it below its rated flow, but 115 L is Fluval's stated maximum — for anything larger the C3 or C4 give you the flow headroom without needing more frequent cleaning.

What's the clog indicator actually measuring?

It's a simple float that rises as the foam pad restricts flow. It tells you when to rinse the pad, not when to replace it.