Description
GLA GRO Planted Aquarium CO2 Regulator
Precise CO2 control in a compact, easy-to-use design.
The GLA GRO Aquarium CO2 Regulator combines piston-type pressure regulation, precise CO2 adjustment, and automatic operation in a compact design. Its integrated components make it easy to control and monitor CO2 delivery without requiring a large regulator assembly.
GRO can supply a single planted aquarium or multiple aquariums with the optional GRO CO2 Splitter. Each regulator is individually inspected, pressure tested, and leak checked in the USA before shipment.
At a Glance
- Pressure Regulation: Precision piston-type mechanism
- Cylinder Connection: CGA-320 standard USA CO2 cylinders
- CO2 Adjustment: Precision needle valve
- Automation: Integrated electric solenoid
- Monitoring: Working-pressure gauge and bubble counter
- Expansion: Optional GRO CO2 splitter for multiple aquariums
Best For
- Single planted aquariums of various sizes
- Compact installations where equipment space is limited
- Aquarists who want precise CO2 adjustment and automatic timer control
- Existing CO2 setups using compatible CGA-320 cylinders
- Multiple aquariums with optional GRO splitter expansion
Why Choose the GLA GRO?
GRO combines the essential components for precise, automated CO2 delivery in one compact regulator. Here's what its features do for your aquarium setup.
- Piston-Type Pressure Regulation: Reduces cylinder pressure to a stable, adjustable working pressure for consistent CO2 delivery.
- Precise CO2 Adjustment: The needle valve allows fine control of CO2 flow and can be rotated 360° for convenient positioning.
- Automatic CO2 Control: The integrated solenoid lets you turn CO2 injection on and off automatically using a timer or compatible controller.
- Easy Monitoring: The working-pressure gauge displays regulator output pressure, while the bubble counter provides a visual reference for adjusting CO2 flow.
- Integrated Protection: A pressure relief valve provides additional protection, while the bubble counter check valve helps prevent aquarium water backflow. Micron filtration helps protect internal regulator components.
- Durable Construction: An aluminum regulator body, precision metal-on-metal valve seat, and quality pneumatic components are designed for long-term use.
- USA Inspection & Testing: Every GRO regulator is individually inspected, pressure tested, and leak checked in the USA before shipment.
What's Included
- GLA GRO CO2 Regulator
- Integrated electric solenoid
- Integrated working-pressure gauge
- Precision adjustable needle valve
- Integrated bubble counter with check valve
- GLA OEM CO2 tank seal
What You'll Need Separately: A compatible refillable CO2 cylinder, CO2-resistant tubing, and a diffuser, inline atomizer, or reactor are required to complete your CO2 installation. These items are sold separately.
Need a cylinder too? Explore our GLA GRO Complete CO2 System, which includes the GRO regulator, a refillable aluminum CO2 cylinder, and selected installation components.
Optional Multi-Aquarium Expansion
The optional GLA GRO CO2 Splitter allows one GRO regulator and CO2 cylinder to supply multiple planted aquariums.
Each splitter outlet has its own precision needle valve, so you can adjust the CO2 flow independently for each aquarium without replacing your existing regulator.
Technical Specifications
- Model: GLA GRO Aquarium CO2 Regulator
- Pressure Regulation: Piston-type mechanism
- Cylinder Connection: CGA-320, standard USA CO2 cylinders
- Adjustable Working Pressure: 0–70 PSI
- Pressure Monitoring: Integrated working-pressure gauge
- Needle Valve: Precision, 360° adjustable
- Automation: Integrated electric solenoid
- Bubble Counter: Integrated, with check valve
- Pressure Relief: Integrated pressure relief valve
- Regulator Body: Aluminum construction
- Valve Seat: Laser-precision metal-on-metal
- Filtration: Multi-stage micron filtration at inlet and outlet
- Multi-Aquarium Expansion: Optional GLA GRO CO2 Splitter
- Quality Control: Individually inspected, pressure tested, and leak checked in the USA
The GLA Difference
20 Years of CO2 Expertise. A Commitment That Goes Beyond the Equipment.
For 20 years, Green Leaf Aquariums has specialized in CO2 equipment for planted aquariums. Throughout that time, we've remained committed to advancing the quality, precision, and reliability of aquarium CO2 regulation. Our experience, long-standing manufacturing partnerships, and close relationships with our customers have helped shape the equipment we offer today.
We don't believe in standing still. We work closely with our manufacturing partners to continually refine our products, incorporate real-world customer feedback, and introduce meaningful improvements. From precise piston-type regulation to advanced dual-stage designs and modular expansion, GLA has consistently worked to raise the standard for aquarium CO2 equipment through thoughtful engineering and innovation.
Every GLA CO2 regulator is individually inspected, pressure tested, and leak checked in the USA before shipment. We take quality control seriously because we understand the importance of dependable CO2 delivery and the trust our customers place in our equipment.
But what truly sets GLA apart is the company behind the products. We're a small business with a personal commitment to the people we serve. We take pride in helping customers select the right equipment, answering technical questions, providing installation assistance, and offering knowledgeable support long after the purchase. We're invested in our customers' success, and we genuinely care about their experience.
That commitment is backed by our Limited Lifetime Warranty on GLA CO2 regulators and systems for the original purchaser, covering qualifying defects under our warranty terms.
When you choose GLA, you're investing in more than precision-engineered CO2 equipment. You're choosing two decades of specialized experience, continuous product development, careful quality control, and a business that stands behind what it sells.
Twenty years of experience. A continuing commitment to innovation. A company that stands behind you.
Frequently Asked Questions
What does piston-type pressure regulation mean?
Piston-type refers to the internal mechanism that regulates CO2 pressure. GRO reduces cylinder pressure to a controlled, adjustable working pressure for aquarium use.
What size aquarium can I use GRO with?
GRO is suitable for a wide range of planted aquarium sizes. CO2 requirements depend on lighting, plant demand, circulation, and diffusion equipment rather than aquarium volume alone.
Can GRO supply multiple aquariums?
Yes. The optional GRO CO2 Splitter allows one regulator to supply multiple aquariums, with independent CO2 flow adjustment for each outlet.
Can I use GRO with an inline atomizer or CO2 reactor?
Yes. GRO supports common planted aquarium CO2 diffusion methods, including in-tank ceramic diffusers, external inline atomizers, and compatible reactor systems.
Does GRO include a CO2 cylinder?
No. This listing includes the GRO regulator and its integrated components, plus the GLA OEM CO2 tank seal. The cylinder, CO2-resistant tubing, and diffusion equipment are sold separately.
Which CO2 cylinders are compatible?
This GRO model uses the CGA-320 connection for compatible refillable CO2 cylinders commonly used in the USA.
Pre-Sales & Installation Support
GLA provides expert pre-sales assistance, equipment compatibility guidance, and installation support by email and text. Whether you're selecting accessories or setting up your CO2 regulator, we're here to help.
Support & Warranty
GLA Warranty: GLA CO2 regulators include a Limited Lifetime Warranty on qualifying mechanical manufacturing defects and a 2-Year Limited Warranty on qualifying electrical manufacturing defects. Coverage applies to the original purchaser and is non-transferable. For complete systems, regulator warranty coverage does not automatically extend to cylinders, tubing, or other accessories.
Service & Returns: GLA prioritizes repair whenever practical. CO2 regulators and systems are not eligible for voluntary returns. Warranty claims require GLA evaluation and authorization before equipment is returned for service.
For complete coverage, exclusions, service procedures, and domestic and international warranty terms, review our Shipping, Returns & Warranty Policy.
Customer Reviews
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My first co2 system success!
I finally caved and went with co2. Upon advisement of my colleagues to contact GLA for a complete system. I sent several emails for 3 days to make sure I was getting exactly what I needed. They were patient and very helpful. They were supportive even during the journey of my aquascape. They were with me every step of the way. I have never recieved this level of service for anything. Not even buying my own home. Cheers to GLA and team, you guys are wonderful and this co2 regulator makes my aquascape glow with brilliance.
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Quality
Great regulator, I would have gone dual stage if I purchased my first regulator again. Only thing I did not like was that the instructions did not say the solenoid could rotate so I was confused installing it because the tank was in the way. quality durable feel and smooth knob operation and co2 production.
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GLA GRO Regulator
Well made and engineered. Easy installation and the regulator works like a charm.
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Lovely aquarium co2 regulator.
Loving my new GLA Gro regulator. Compact and heavy duty. Instructions were very easy to follow. Up and running in just a few minutes. Rock solid.
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Aquarium co2 regulator for any co2 cylinder type.
That is precisely why I went this way. Im starting out with small disposable bottle but I know I will be moving to a 5lb next year. This compact regulator is surpassingly very heavy. The bubble counter and needle valve are very smooth and effortlessly adjust where you need it.
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Compact workhorse!
Compact,precise and well made. Cant ask for more than that. Great price and good service.
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Brilliant co2 regulator.
Wonderfully crafted compact co2 regulator. My main reason for this purchase was that this regulator will work on any cylinder type using GLA adapters. Very sleek design and the unit weighs like brick. Beautifully packaged I must say. Tune-ability of the bubble rate easily done by the precision needle valve. I plugged the solenoid into a bluetooth timer and that was that, ready! Cheers, Simon
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Excellent quality speedy delivery.
Great co2 regulator for my 80g. I wanted something that came with customer support and GLA's service was second to none. Fancy packaging and easy installation. Your going to love your GLA regulator.
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High quality co2 regulator.
My first time using co2 in my planter aquarium and things are growing great. Super easy install and wonderful quality. I didn’t get the drop checker they recommended but I totally needed it and ordered one the next day. Make sure if this is your first time that you use a drop checker. It will be your guiding light to adjusting your co2 levels.
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Excellence in a compact co2 regulator.
I love this thing. The best part is it fits all cylinder types. You will need to order tubing, keep this in mind. I had it up in running in 5 minutes, its perfect.
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Amazing Co2 Regulator
I have tried all the brands and GLA is the best quality product
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Solid Regulator
I had originally purchased a regulator on Amazon for my setup. While that one did work, it felt flimsy and I had to tighten the solenoid every time I switched out tanks. I just wanted something I had more confidence in in the long right. Confidence in your equipment is a big deal when you have so much money invested in a tank that relies on it. So I went with this one and could not be happier. It feel more durable and was easier to get the bubble count correct compared to my previous regulator. While I have only had this one in use for a couple weeks now, I have had no issues.
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I love it
I run this regulator on a 90g tank and so far its been great. I like that it will work on every type of cylinder on the market. Should my tank plans change this regulator is super flexible. Although its not modular like the DS model it still uses the same guts. Thank you GLA.
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I love this regulator.
What a terrific regulator, exactly what my tank needed. It came with everything in the box you would need to install and get moving. Came with all the tools to install and even service it in the future. Installing it was super easy, only a fe w minutes as the instructions are super easy to follow. I also found this helpful,https://www.youtube.com/watch?v=K_Sv5Vb4yfg&t=53s You will be extremely happy with your Gro regulator, top notch.
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Super build and quality
I got this for my calcium reactor and its all I could ask for. Compact,heavy duty and uses legit water tight chord grip.
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Quality matters
No more headaches from nasty finicky needle valves. Moving to a high end needle valve is an amazing feeling. It just works.
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So far am very pleased
I received my regulator 2 weeks ago and must say I am very pleased so far. My old regulator had a crap needle valve and would dump CO2 into my tank sometimes. After installing this regulator and also getting a new co2 diffuser (I got a metal one since I broke the glass one when taking it out for a cleaning), my plants are looking quite happy and there is a steady stream of bubbles into the tank daily that I haven't really had to adjust. I will say an improvement to the design could be painting arrows on the dials to indicate which direction to turn the valves in- not gonna lie that confused me very much upon installation. Also, there was one day where I set the pressure for 40 ppm? and the next morning it was at 20 ppm. However, that could have been other factors and not the regulator's fault. Anyway, overall so far I am very glad I spent the money on this regulator! Also, GLA's customer service was helpful. __________________________ Reply: It was a pleasure helping you with your co2 system. When setting up its critical to always adjust your PSI with the solenoid activated in the off position. This will keep any upstream pressure from effecting physical adjustment of the psi gauge. Its a basic mistake we see made often. However no harm no foul because it can not damage anything. It only takes basic procedure know how and the rest is breezy. Thank you for your trust and support! Best, Laura @ GLA-Team
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Great quality,simple to set up
Cant think of anything i could possibly critique, the regular was delivered quickly, went together quickly and easily, and is keeping my co2 levels perfect for my plants
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Beautifully made, sturdy, and functions immaculately
One of the more well made pieces in my setup. Too bad it has to hide in the cabinet. This regulator feels sturdy, and the dials are well made and so smooth. Highly recommended.
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Excellent co2 regulator
I bought this regulator along side a GLA DS series co2 regulator. I use this one on a 10g tank that has a small cabinet space so I needed something compact. I was not totally sure what to expect when it arrived but I can say this co2 regulator has a really nice build quality. The needle valve was super easy to adjust, install was almost thoughtless. I had it installed in under 5 minutes. This co2 regulator was above and beyond my expectations. GLA service was second to none to boot.
