FZONE 2.5L Upgraded Aquarium CO₂ System with Complete Accessories, CO₂ Generator kit with Integrated Solenoid & Bubble Counter, Safety Valve, Main Switch for Planted Tanks
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Availability:
In Stock.
Arrives
Friday, Feb 27
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Size: 2.5L
Features
- High-Efficiency CO2 Supply System: FZONE CO2 generator system uses a citric acid and sodium bicarbonate reaction to produce high-purity CO2, delivering stable pressure and flow through a CO2 regulator, bubble counter, and CO2 diffuser. Unlike traditional cylinder systems,it requires no refilling at CO2 stations, making it more convenient
- Enhanced Safety Design: The FZONE aquarium CO2 system is made from food-grade 304 stainless steel with body 50% thicker for greater strength and pressure resistance. The CO2 system includes a manual shut-off valve for safe control when CO2 is not needed, and an automatic pressure-relief valve that releases excess pressure when it rises above the safe limit,providing dual safety protection for worry-free operation.
- Precise and Reliable CO2 Control:The FZONE CO2 generator for plantsuses a precision needle valve for smooth, accurate flow adjustment. The bubble counter provides a clear view of CO2 injection rate, while the pressure gauge displays real-time tank pressure. Its upgraded all-in-one solenoid minimizes connections and leak risks, ensuring stable, consistent CO2 delivery for your planted aquarium.
- Ready to Use: This complete Aquarium CO2 kit is designed for easy setup and convenience. It includes all essential accessories CO2 diffuser, check valve, U-connector, suction cups, tubing, funnel, syringe, sealing rings, and power adapter no extra parts required. Just add the raw materials (not included) and youre ready to go.
- Easier Use and Maintenance :The DIY co2 reactor kit features an upgraded external thread design that prevents residue buildup, making cleaning simple and smooth. The bottle opens effortlessly without sticking, and the built-in fill port lets you add water directly with a syringe no need to unscrew the cap, saving time and effort.
Package Dimensions : 14.68 x 13.19 x 4.92 inches; 4.5 Pounds
Item model number : FZ-GNRT
Date First Available : September 17, 2025
Manufacturer : FZONE
Best Sellers Rank: #32,293 in Pet Supplies (See Top 100 in Pet Supplies) #118 in Aquarium Air Pump Accessories
#118 in Aquarium Air Pump Accessories:
Customer Reviews: 4.5 4.5 out of 5 stars (28)
Item Weight: 4.49 pounds
Manufacturer: FZONE
Item model number: FZ-GNRT
Date First Available: September 17, 2025
Item Package Dimensions L x W x H: 14.68 x 13.19 x 4.92 inches
Brand Name: FZONE
Warranty Description: 1
Model Name: CO2 Generator
Color: Silver
Size: 2.5L
Number of Items: 1
Included Components: CO₂ Generator kit
Specific Uses for Product: Planted aquarium
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Friday, Feb 27
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Top Amazon Reviews
Size: 2.5L
I’ve run my DIY yeast and baking soda CO2 when I just started this hobby. Recently, I became more high-tech and started using injected CO2 systems. The FZONE 2.5L CO2 Generator System has honestly impressed me more than I expected. If you’ve been in the hobby long enough, you know that a CO2 setup is only as good as its stability, build quality, and fine control. This unit delivers on all three. Build & Design: The stainless steel body feels solid and professional, not flimsy like some DIY kits. All the seals, connections, and threads are tight and precise. It’s the kind of system where the moment you pick it up, you know it's engineered properly. The pressure gauge is clear and responsive, and the bubble counter has no lag or micro-leaks. Performance: What surprised me most is how consistent the output is. Many smaller generators fluctuate, but this 2.5L model holds pressure beautifully throughout the diffusion cycle. I get a steady bubble rate all day, which is crucial when you’re maintaining demanding plants like Rotala species and carpeting plants. Ease of Use: Setup was refreshingly straightforward. The instructions are clear, and everything you need is in the box. If you’ve ever assembled a DIY citric acid/baking soda rig, this feels like an upgraded, frustration-free version: safer, cleaner, and much more predictable. CO2 refills take just a few minutes, and I can run my 16-gallon tank for weeks before topping up. Efficiency: I pair this with a good inline diffuser, and the gas dissolution is fantastic. My pH drop is consistent, growth is explosive, and algae has backed off significantly. Don't believe me? Look at the pictures and judge for yourself. That's my tank with the CO2 paired with the Fzone Brite light. Honestly, if your plants aren’t thriving with this system, it’s not the CO2. Value: For the performance you get, the price is almost too good. You’re basically getting near-pressurized-cylinder stability without the hassle of renting tanks or lugging them around for refills. Final Verdict: If you’re a planted-tank hobbyist who cares about healthy, vibrant growth - and you want a reliable CO2 system without breaking the bank - this is one of the best setups you can buy. After years of using everything from regulator kits to full pressurized cylinders, the FZONE 2.5L generator has earned a permanent spot in my aquarium rotation. Highly recommended for beginners AND seasoned aquascapers.
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Reviewed in the United States on November 19, 2025 by joe joe
Size: 2.5L
Fzone CO2 generators are my go to for CO2 injection. I have a 75g, 29g, & 16g tanks all running Fzone generators. My 29g has the original 4l version that I purchased a while ago and has been running flawlessly. When they approached me about trying their new upgraded 2.5l kit I was excited to see if they addressed they few complaints I had with the original version. The new upgraded version has definitely improved for my set up. Most noteably, the instructions on the upgraded kit are vastly improved. The original instructions were very confusing and I had to source additional information online about the setup. On the new version, they are much clearer on how to set it up, what chemicals are needed, and how much to use. For someone who is purchasing their first setup, you should have no problems if you read them thoroughly. The second major improvement, which may not affect everyone, is the reduction in overall height. I am now able to fit both the larger 5l and the 2.5l in my cabinet. My original 4l was too tall to fit. The included parts are all very high quality and the diffuser included in the upgraded kit has a much larger surface air and produces much finer bubbles. The included CO2 tubing is much more flexible and easier to work with than the original. The new bubble counter has a fill port on the side of it as well as a small syringe so you don't have to remove it from the solenoid assembly when the water evaporates. I found this to be very fiddley and I had to have the angle of the syringe perfect or it would leak. I didn't find this method any easier than unscrewing the bubble counter to fill it and I probably won't use it again. The value of these generators can't be beat and he quality of the parts are excellent. No need to waste time driving to get tanks filled. I get about 3 months of run time on my original 4l setup. I expect to get about 6 weeks on this 2.5l setup. I bought bulk citric acid and baking soda here on Amazon and just keep it on hand for when I need to fill them back up. Over all, I highly recommend these kits. I will not hesitate to purchase more if I expand my tank collection. I'd like to see a 1l desktop setup so I can add CO2 to my nano tanks. I'd buy 3 immediately!
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Reviewed in the United States on December 12, 2025 by Dougie Fresh Dougie Fresh
Size: 2.5L
Very easy to set up and install. Directions were clear, size is perfect to fit out of the way. The solenoid valve works great and was extremely easy to throw on a smart outlet to pair up with my lighting schedule. The bubble counter was also very easy to dial in and comtrol. Overall, extremely happy with the setup 👍.
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Reviewed in the United States on November 22, 2025 by Amazon Customer Amazon Customer
Size: 5L
So far I am not pleased. The solenoid does not turn off the co2 when unplugged and the instructions are horrible. I had to look up videos online and turns out the mixures are all incorrect also. This system works well otherwise and if it wasnt for the regulator and solenoid issues I would have given 5 stars. I ordered a replacement so I will see if this one is just faulty and update my review. Notice the solenoid light is off in the picture but still getting bubbles. Update: I received a new bubble counter and it's better but still leaks. What I did was close the main valve almost all the way to lower the pressure greatly and it seems to be working now. The solenoid valve is just too weak to hold a lot of pressure. I have the system working well but it was a bit of work adjusting everything correctly.
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Reviewed in the United States on November 26, 2025 by Metabolic Metabolic
Size: 2.5L
The media could not be loaded. What a great kit! The two most important items (the canister and the regulator) are high quality, sturdy, and feel reliable. I’m happy to report that the fine-tuning valve works as designed. I personally have this setup connected to a smart-plug, and it’s presented no issues. In addition to the most crucial items, this kit comes with tubing, a check valve, suction cups, a diffuser (which I’ve yet to put in a tank but can confirm that it works and produces tiny bubbles), a stand for the canister, and even a funnel. So, basically, you’ll only need to buy the ingredients (baking soda and co2). Hats off to FZONE.
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Reviewed in the United States on January 5, 2026 by Justin Martin Justin Martin