Pro Leaf CO2 Regulator - Solenoid Gas Regulator for CO2 Cylinders
Best for: growers running bottled CO2 enrichment who need a regulator to control gas release from the cylinder.
Our thoughts
CO2 enrichment only works if the dosing is controlled properly, and that's exactly what a regulator like this is for - it sits between your cylinder and your grow space, releasing gas only when it's told to. Solid brass construction rather than cheap plastic fittings, which matters given it's handling pressurised gas.
The Pro Leaf CO2 Regulator fits directly onto a CO2 gas cylinder and uses an industrial solenoid valve to release gas only when instructed, rather than allowing it to flow continuously. It's built from solid brass and includes a precision flow gauge, two pressure dials (one for gas pressure, one for flow rate) and 5 metres of plastic dispensing tube, and it can safely release up to 17 litres of CO2 per minute.
On its own, the regulator doesn't decide when to dose - it's controlled by a separate CO2 controller (such as the Pro-Leaf CO2 Controller & Sensor), which sets the target CO2 level and tells the regulator's solenoid valve when to open and close. The valve stays open only until the pre-set CO2 level or dosing time is reached, which keeps levels in the grow space safe and consistent rather than risking a build-up of excess CO2.
How it compares
CO2 regulators are a fairly standardised product category, built around a solenoid valve and pressure gauges - the differences tend to come down to build quality and included accessories.
- Compared with generic aftermarket CO2 solenoid regulators sold for aquarium or grow use, the Pro Leaf's solid brass build and included 5m dispensing tube make it a more complete, ready-to-fit package.
- Compared with Titan Controls CO2 regulators, both use an industrial solenoid valve and dual-gauge setup, with brand and bundled accessories being the main differences.
- Compared with running CO2 without a regulator at all (i.e. releasing straight from the cylinder), a proper regulator is what makes safe, controlled dosing possible in the first place.
This isn't a product you can meaningfully cut corners on, given it's regulating pressurised gas - solid brass construction and a sensible flow rate are what you actually need here.
Usage guidance
The regulator needs to be paired with a CO2 controller to actually manage dosing.
Installation
Fit the regulator directly onto your CO2 cylinder, connect the dispensing tube to route gas into your grow space, and wire the solenoid to your CO2 controller.
Controller pairing
The regulator itself doesn't set target CO2 levels - use it alongside a CO2 controller such as the Pro-Leaf CO2 Controller & Sensor, which tells the solenoid when to open and close.
Safety checks
Check hose and fitting connections regularly for leaks, and never run CO2 enrichment in an occupied space without adequate ventilation and monitoring.
Technical specifications
- Construction: solid brass body, industrial solenoid valve
- Max flow rate: up to 17 litres CO2 per minute
- Gauges: gas pressure gauge and flow rate gauge
- Included tubing: 5 metres plastic dispensing tube
- Fitting: fits directly onto CO2 gas cylinder
- Control method: requires a separate CO2 controller to set dosing/target levels
- Brand: Pro Leaf
Who this is for
- Growers running bottled CO2 enrichment who need a regulator for the cylinder
- Anyone upgrading from an uncontrolled CO2 release setup to a proper regulated system
- Growers already running a Pro-Leaf CO2 Controller who need the matching regulator
- Larger grow spaces where consistent, safe CO2 dosing makes a real difference to growth
Our take
A properly built brass regulator with a sensible flow rate and dual gauges - exactly what you want handling pressurised CO2 gas, rather than a flimsy plastic fitting.
Does exactly what it should, day in, day out - pair it with a CO2 controller and you've got a safe, properly regulated enrichment setup.
