• Fully external — the reactor body, and all CO2 dissolution, happens outside the aquarium. Nothing to hide inside an aquascape.
• Hermetically sealed housing — CO2 stays in the reactor chamber under water pressure instead of gassing off at the surface, which is the main efficiency loss in inline diffusers.
• Universal mounting plate — fixes to a cabinet wall or sits loose behind the tank; no fixed orientation requirement.
• 16 mm hose connection — matches Aqua Medic's standard hose barb sizing, so it plumbs inline with common external pump and canister filter hose runs.
• Serviceable — O-rings, hose nozzles and the deaeration valve are all available as spare parts, so a worn seal doesn't mean replacing the whole unit.

The 2,000 L rating is a ceiling set by CO2 contact time, not by physical size. What actually determines performance is the flow pushed through the reactor: Aqua Medic specifies 1,500–2,500 L/h. Below that range, CO2 has too long a contact time and can supersaturate the outflow; above it, contact time drops and dissolution efficiency falls. Check your external pump or canister filter's rated flow against this range before ordering — a pump sized only for the display tank's turnover may not fall inside it.

The box contains the reactor body, mounting plate and hose nozzles for a 16 mm connection. It does not include a CO2 cylinder, regulator, solenoid, bubble counter or the external pump that drives water through it — all of these are sold separately and are required for the reactor to function.

• Suitable for: planted freshwater aquariums already running, or being fitted with, an external pump or canister filter capable of 1,500–2,500 L/h through a bypass line.
• Not suitable for: tanks without a pump able to reach that flow window, and marine/reef systems — this is a CO2 reactor for planted tanks, not a calcium reactor.

Check the deaeration valve periodically for trapped air, which reduces the water volume in contact with the CO2 and cuts dissolution efficiency. O-rings and hose nozzles are wear items and are sold individually if a seal starts to weep.

Covered by Aqua Medic's manufacturer warranty against manufacturing defects, in addition to your rights under Australian Consumer Law. Standard freight — no special handling required.

Do I need a separate CO2 diffuser as well?

No. The Reactor 1000 replaces an inline or in-tank diffuser entirely — CO2 is injected into the reactor chamber and dissolved there before the water returns to the aquarium.

Can I run it on my display tank's main filter return?

Only if that pump's flow falls inside 1,500–2,500 L/h. Many display-tank canister filters are sized well under this for a planted tank's turnover, so a dedicated pump on a bypass loop is common.

Will it work on a marine or reef tank?

It's built and rated for freshwater CO2 injection. Reef keepers wanting to dissolve CO2 for a calcium reactor need a calcium reactor, not this unit.

Where does it mount?

Anywhere external to the tank within hose reach — cabinet wall via the mounting plate, or standing behind the aquarium — as long as the 16 mm hose connections reach your pump and return line.

What if I see bubbles collecting inside the reactor?

Small amounts of trapped air are normal and are cleared through the deaeration valve. Persistent air building up faster than it clears usually points to a flow rate below the 1,500 L/h minimum.