Aqua Medic Silicone CO2 Hose - 4/6mm (5mtr pack)

• 4/6mm sizing – fits standard aquarium CO2 fittings without an adapter.
• 5 metre roll – enough for most regulator-to-diffuser runs, with length to spare for routing around a cabinet or sump.
• Flexible – routes around tight corners without a hard kink.

Suitable for connecting CO2 regulators, bubble counters, check valves, solenoids and diffusers that use a 4/6mm barb. Not sized for the larger hose barbs used on some skimmer or reactor plumbing – check your fitting size before ordering. Aqua Medic doesn't publish a maximum working pressure for this hose, so we can't confirm it against a specific regulator's output pressure.

Trim to length with a sharp blade for a clean, leak-free push-fit. Replace if it hardens, discolours or develops a permanent kink, which reduces flow and can strain a push-fit joint.

Sold as a consumable line item; no separate warranty applies. Standard delivery.

Will this fit my CO2 regulator?

If your regulator, bubble counter or diffuser uses a 4mm barb with a 6mm outside diameter, yes. Check the fitting size stated on your other CO2 components first.

Is this hose gas-tight for CO2?

Aqua Medic sells this as a CO2 line, but doesn't publish an independent gas-permeability or working-pressure figure for it, so we can't give you a number here. For a long-term, low-loss run, keep joins tight and check the line periodically for CO2 loss – a drop in bubble count at the same regulator setting is usually the first sign.

Can I use it with a check valve?

Yes – it's designed to connect standard 4/6mm CO2 components including check valves, in-line diffusers and solenoids.