Name: UNS Pro CO2 Dual Stage Regulator
Brand: UNSCO2
SKU: CO2J005
Price: 219.99 USD
Availability: InStock

UNS Pro CO2 Dual Stage Regulator

$219.99 USD

Usually ships in 1-2 business days from our fulfillment center

This product qualifies for FREE SHIPPING!

The UNS Pro CO2 Dual Stage Regulator is designed for hobbyists looking for a long-term, professional-grade CO2 solution for planted aquariums. Featuring dual gauges for monitoring both working pressure and remaining cylinder pressure, it makes it easy to track CO2 levels and anticipate when a cylinder is running low. Included manifold blocks allow a single CO2 cylinder to supply multiple planted aquariums, making the Pro Regulator an ideal choice for expanding aquarium collections, fish rooms, and advanced aquascaping systems.

Best For
- Medium to large planted aquariums
- Long-term CO2 systems
- Hobbyists using refillable CO2 cylinders
- Multi-aquarium setups
- Aquascapers looking for more control and consistency

Why Choose the UNS Pro Regulator?

Dual-Stage Reliability: Dual-gauge regulators are sometimes referred to as dual-stage thanks to an extra fail-safe stage that prevents “end-of-tank dump” (a sudden release of CO2 when a cylinder is running low). This built-in feature keeps CO2 levels more stable and helps prevent sudden fluctuations.
Expandable for Multiple Aquariums: The included bubble counter manifolds allow CO2 to be distributed across multiple planted aquariums from a single cylinder. Additional manifolds can be added as your aquarium collection grows (we recommend up to 8 splits).
Compatible with Standard Refillable Cylinders: Designed for use with CGA-320 CO2 cylinders ranging from 2.5LB to 20LB, providing a practical long-term solution with fewer refills and lower operating costs compared to disposable options.
Beautiful Design: Finished in an anodized Space Grey, the Pro Regulator offers a clean appearance that complements planted aquarium equipment and cabinetry.

The UNS Pro Dual Stage Regulator is intended for hobbyists ready to invest in a dedicated pressurized CO2 system. While larger than cartridge-based alternatives, it offers greater stability, longer refill intervals, and the flexibility to expand over time.

Product Compatibility
- Standard CGA-320 CO2 cylinders (UNS Pro Cylinders)
- CO2-proof tubing
- Aquarium diffusers
- Inline diffusers
- Bubble counters

What’s Included
- UNS Pro CO2 Dual Stage Regulator
- CGA-320 Adapter
- 2 Bubble Counter Manifolds
- Power Adapter
- Assorted O-Rings (extra replacements included)
- Installation Tools

Learn about other CO2 regulators and find the best solution for your planted aquarium. Shop All CO2 Regulators

Ultum Nature Systems creates premium aquarium products designed by hobbyists, for hobbyists. Known for thoughtful design that first appeared in their line of rimless aquariums, they continue to move ground in the industry, with the health of your aquarium always at the forefront. Since the release, the brand has expanded into a variety of aquarium needs and everyday essentials that fuse form and function.

From best-selling substrates like Controsoil and Controsand to powerful filtration systems and nutrient-packed aquatic plant fertilizers for aquascapes at every stage, you're sure to find something you didn't know you needed. Jump further in and browse CO2 gear, various natural hardscape choices, then pick up some live aquatic plants and the tools you need to plant, maintain, and keep your tank looking its best. With a recent venture into the world of marine, UNS supports today's aquarium hobbyists every step of the way.

Inspired by nature and powered by the art of aquascaping, plan your next aquarium project with Ultum Nature Systems today.

Shop all UNS

Ultimate Planted Aquarium CO2 Guide

Adding CO2 to a planted tank might seem complicated at first—with all the gear and technical terms, it’s easy to feel overwhelmed. However, once you understand the basics, setting up a CO2 system for your planted tank is just as straightforward as setting up a filter or light. We’ll walk you through everything you need to know step-by-step.

Aquario Neo CO2 Diffuser Normal Large injecting micro CO2 bubbles

What is CO2 and why is it important in a planted aquarium?

Just as we need oxygen to survive, aquarium plants rely on carbon dioxide to thrive. CO2 is naturally produced by fish, humans, and other animals, providing plants with what they need. In a freshwater tank, fish naturally produce small amounts of CO2, which can give the impression that some aquatic plants don’t need it. In reality, all plants require it, just at different levels. This is why CO2 injection systems are strongly recommended—Popular beginner plants like Anubias, Bucephalandra, Java Fern and aquatic mosses are commonly labeled as “low-tech” because they can handle minimal levels. However, even hardy plants benefit greatly from added CO2 and will grow more quickly and vibrantly with it.

Aquascaper’s Notes: During photosynthesis (lights on), plants release oxygen, which helps keep the water well-oxygenated for livestock. As a result, most aquascapers skip traditional airstones or bubblers.

Easy beginner low light aquarium plant Java Fern Trident

Microsorum pteropus AKA Java Fern 'Trident' producing oxygen

Okay, so aquarium plants need CO2, but what does it really do?

For proper growth, aquatic plants require a balanced mix of light, nutrients and CO2. Think of it like a pie—each slice represents one of these elements. If any slice is too small, large or missing, the pie is incomplete and represents an imbalance aka ideal conditions for algae to take over. Injecting CO2 into a freshwater planted tank improves plant health, and stability. That’s why we recommend CO2 systems even in low-light or beginner-friendly tanks. It completes the pie, creates balance and reduces the risk of algae problems.

Common examples of planted aquarium imbalances:

Too much light, but not enough CO2 or nutrients
Too much nutrients, but not enough CO2

What equipment do I need to start injecting CO2?

The process is simple, once you understand must-have gear. Here are our four essentials every planted tank hobbyist should have.

1. CO2 Regulator

Controls overall output levels. Each regulator will have at least one gauge that will display the maximum output pressure. We typically set this anywhere between 25-40PSI (safe range) on the main valve and fine-tune the flow with the needle valve (the smaller one) to dial in levels being injected. Dual-gauge regulators show both working pressure and available gas reserves in the cylinder. Higher-end models may also include a solenoid. A solenoid lets you shut off CO2 manually or with a timer—usually synced with the lights, since aquarium plants will not require it when lights are off.

Shop UNS Mini CO2 Dual Stage Regulator CO2 - Glass Aqua

Almost all CO2 regulators will have a gauge that displays maximum output pressure

While other CO2 regulators will have dual gauges

Main pressure valve on an Ultum Nature Systems Mini CO2 Regulator

Needle Valve on an Ultum Nature Systems Mini CO2 Regulator

Ultum Nature Systems UNS Dual Gauge CO2 PRO Regulator for Planted Aquariums

CO2 Regulator solenoid example

2. Cylinders & Cartridges

These store CO2. How long do they last? This is one of the most common questions we get—and the honest answer is: it depends. Every aquarium is different. Factors like tank size, aquarium water chemistry, plant variety, plant density, and CO2 injection levels needed all impact how quickly a cylinder or cartridge is used up. Here are some guidelines:

Cartridges: Single use, compact and convenient. They are the perfect desktop solution for nano tanks between 1 - 8 gallons.
Paintball Cylinders: Budget-friendly option that is popular for convenience, size and ease of use. Most can be refilled at related hobby (paintball) stores. A great option for aquariums up to 20 gallons.
Standard CGA-320 Cylinders: Don’t let the name intimidate you! A CGA-320 is a North American standard that can be refilled at most welding, air-supply or local brewery shops. This is our top recommendation for all aquascapers who are invested in the planted tank hobby. This type of cylinder holds the most and will require less refills in between uses.

Planted Aquarium CO2 Injection Equipment

3. CO2 Diffuser

Delivers CO2 in the form of ultra-fine bubbles into the aquarium. Some aquarium airstones may look similar to CO2 Diffusers, but these aim to produce larger bubbles for surface agitation and gas exchange. The larger the bubbles, the more the aquarium will be oxygenated. CO2 needs to be easily dissolved in a planted aquarium, which means the smaller the bubbles, the better.

4. CO2-Proof Tubing

This is important. Normal airline tubing for aquariums cannot handle the higher pressure of CO2 systems. Specialized CO2 proof tubing is built to withstand pressurized CO2 and allows it to travel safely into an aquarium without leaks.

Ultum Nature Systems Pro CO2 Tubing | Planted Tank CO2 - Glass Aqua

Optional CO2 Equipment

1. Bubble Counter: Not required, but a helpful tool! Bubble counters provide a visual reference in the form of bubbles for how much CO2 is being injected into the tank.

2. Drop Checker: This small glass accessory hangs on the rim of the tank or suctioned to a glass panel inside the aquarium. They typically include a liquid solution that changes colors based on the amount of CO2 injected.

Yellow means too much CO2, blue indicates too little, and green means the levels are just right. It can take a few hours following installation or a water change to change colors!

Ultum Nature Systems Micro CO2 Bubble Counter | CO2 - Glass Aqua

Ultum Nature Systems UNS CO2 Drop Checker

If you’ve read this far, we hope you now have a better grasp on planted aquarium CO2 injection. If you’re still not sure and a full setup feels like too much, we recommend starting out with a simple CO2 Kit. It’s easy to use, beginner-friendly and great for many tanks! But if you’re ready to make that leap and full send into CO2 injection, check out our bundled CO2 Kits at discounted prices. As always, if you have any questions, our team is always happy to help!

Shop Planted Tank CO2 Kits

Overall rating: 5.0 / 5 from 9 reviews.

AI Generated Review Summary

Summary topics

Review topics: ["regulator","cylinder"].

Review highlights

Reviews

"Never used co2 before but i watched all the YouTube set up videos, the product came exactly the way it was advertised."

— Dylan (5/5)

"Excellent"

— José E. (5/5)

CO2 Regulator you Need

"I use this regulator for my UNS 60U aquarium, and it works great! The installation is a breeze. There are two YouTube videos from UNS that explain the setup and maintenance quite well. The regulator comes with 2 bubble counter manifolds, but it's very easy to disconnect one if you need only one. One piece of advice I would give to other beginners is actually regarding the CO2 cylinder itself. Before buying a nice-looking cylinder from UNS, I recommend doing some research to find a store where you will fill the cylinder with CO2, since it will come empty. The nuance there is that it is very likely shops will not fill the cylinder you bring, but instead tell you they can only replace it with the one they have in store. In this case, it is better to buy a cylinder from the store. This will be cheaper, though their cylinder will not look as nice. If you manage to find a store that can refill your cylinder, that's great!"

— Alexander F. (5/5)

Perfect regulator to run inline

"Perfect regulator to run inline CO2 injection in both canister filters for my new 118 Gal tank."

— Bicknell R. (5/5)

Very easy ti set up

"Very easy ti set up"

— Raymond C. (5/5)

Solid experience

"Quick shipping, exactly as advertised"

— Jacob W. (5/5)

Works perfectly

"Expensive but can't beat the quality. Worth the money"

— andrew c. (5/5)

Well designed CO2 dual stage/dual bubbler regulator

"Well designed and well made regulator in this price range. 1st unit had issues with maintaining 2nd stage (low-pressure side) pressures over 30 PSI, but the outstanding team at Glass Aqua walked me through a very thorough troubleshooting process to identify and resolve the problem. Highly recommend the company, Glass Aqua, for any of your equipment needs, they know their gear!"

— Stephen J. (5/5)

Good regulator

"This is my second regulator like this. I like that I can connect extra manifolds to supply all my tanks. This is a very good deal. On the first one I had to fix the solenoid that came with it but otherwise no problems with these regulators."

— Monika A. (5/5)

Q&A

Shipping
Orders are typically processed within 1-2 business days M-F. However, additional time may be required during peak seasons and federal holidays. For orders containing live plants, we exercise extra caution and assess factors such as travel distance and weather to ensure safe transit.

To avoid delays, please ensure all order information is accurate and complete. We cannot offer refunds and are not responsible for orders shipped to incorrect addresses due to errors in provided information. Once an order has been shipped, delivery times are determined by the carrier and are outside of our control. On average, shipments arrive within 2–5 business days, excluding weekends and holidays. For more information, please visit our FAQ page.

Returns
If you are not satisfied with your purchase, please contact us within 48 hours of delivery. Approved returns must be shipped back within 14 days of approval. Returned items must be unused, unopened, and in their original packaging. Specific return requirements, if applicable, will be listed on the product’s page. For more information, please visit our FAQ page.

Refunds
No worries, we’ll take care of everything as long as it fits the guidelines above.Most answers to general questions can be found on our FAQ page.