Fzone 5.5 L Aquarium CO2 System Generator Kit for Aquarium Plants Tanks

I'm a first time CO2 user and this is my second venture into the aquarium hobby. My first go round, I always wanted an nice lush planted tank but I was in my early teens and couldn't afford the size tank or the items required for that kind of setup. Now on my second go round, I decided to follow that path of my dream aquarium and with that came the initially overwhelming prospect of CO2 systems. The Fzone CO2 generator system has made that very simple and significantly less daunting for me. It comes with almost everything that you need to set up the system. The only things the system doesn't come with is sodium bicarbonate, citric acid, a digital scale, or check valves. I highly recommend you spend a couple dollars on check valves. Those check valves will keep water from backflowing into the co2 lines when you have the system off. If you want to make your life super simple, you will need them. They also allow you to easily disconnect the bubble checker when it comes time to refill the bottle with your baking soda and citric acid. Now, I did say I'm new to CO2 so I did make a mistake when filling the bottle. The directions specifically state to hold the bottle at a 45 degree angle when filling. I did this until I went to grab the cap. When I reached for the cap of the tank I set the canister straight up, which meant I ended up having a fountain of the chemical reaction shoot out of the top of the tank until I was able to screw the cap onto it. Don't make the same mistake I made. That was my own mistake I made, like I said I knew it had to be held at an angle and I had an airheaded moment. Now I will say, if you have a larger tank, go for the 5L kit. I have a 75 gallon and I have had the CO2 on a timer, and my tank pressure has gone from 400+ PSI when freshly full to 150 PSI in 4 days. I will most likely need to upgrade to the 5L bottle here in the next month or so, but I also have my system running for 11hrs a day. As stated, the tank pressure goes up to over 400PSI, which already tells me that the build quality is quite superb, and I noticed some other reviews state that the knob to adjust the bubble flow was a bit touchy. My specific system was just touchy enough to where it was actually pretty easy to set my flow rate at 3 bubbles a second without really struggling with having to fiddle around with it. The tank is pretty weighty, but I believe that's due to the fact that it is built very well. When you initially fill the tank it will get cold enough to condensate on the outside, but that is due to the chemical reaction. It's not a flaw. Overall the 2.5L was perfect for me to dip my toes into the beautiful world of planted tanks, and is good value for people who have a smaller setup, such as a 29G or less. For my specific use case, I will need the 5L so I don't have to refill every week.

Fzone has fantastic customer support (thank you Cheryl). I was missing the white piece on my filter and they sent me a new filter. I have used an fzone regulator on a paintball tank previously, but I had a stroke, and it's no longer possible for me to go get CO2. Therefore, I looked for a CO2 generator and was happy to find that fzone had this one Because of my previous familiarity with using CO2, despite the horrible instructions, it was quite easy to get set up and get started. This unit came with a solenoid which works perfectly. I have it on a timer to turn on in the morning and shut off at night. I replaced the diffuser with one from clscea (stainless steel, widen hook 25cm) which works much better, especially for rimmed tanks. The supplied funnel's base is too narrow to be of real use (fzone please replace this). This unit no leaks, it's looks great, runs quietly, gives me great value for money, and I have to trim my stem plants more often now and my plants look fantastic Fzone makes great products and I will buy from them again.

No seal problems, all parts there, instructions are mostly good. If you dont have a scale, you'll need to do a little math. I added 13.8 Tablespoons Baking Soda, and 8.3 Tablespoons Citric Acid with my 300ML water and it seems to be working out... but again do your own math and make sure do NOT take my word for it. It's been a few weeks and my plants seem happy and my fish are alive so those measurements haven't killed my 29G just yet... Anyways, the setup seems ideal and is decent price as far as I can tell. It does the job well, and hasn't failed me yet. Seems like it's decently made so I'm happy with my purchace. Would buy from this seller again. On a final note... buy a CO2 drop checker. I did some math and figured 1 bubble per 2 seconds was good.... now I'm using 4 bubbles per 1 second. It will help you figure out how much to be adding to your tank and save you mental stress trying to guess. Just take it SLOW and figure out what rate gets your checker green fastest and keeps it green without going into the yellow (danger) zone.

It’s a pretty solid system. The needle valve is a little sensitive for my taste. It’s not bad but it could be a little better. The materials are all high quality. The system is running well without any issues. The diffuser is a little on the low end. The bubbles are a mixture of good micro bubbles and some larger bubbles. I would recommend getting another one if you want tiny bubbles all around. It’s solid though as none of the bubbles were large. The system was easy to set up. They say use 200 grams of citric acid and 200 of baking soda. Chemistry says you need 200 grams citric acid and 260 grams of baking soda to get a perfect consumption in the chemical reaction based on the mole weight of each. I went with science to avoid having a lot of left over matter when the tank needs to be refilled. You can avoid the crust or unused citric acid some complained about in the tank this way as all the citric acid will be used in the reaction. That’s a pretty minor issue though. All in all, it’s a good build and quality materials. I got some pearling of my plants day one. The price isn’t bad given everything. I would have given 5 stars for a slightly better needle valve and a slightly better diffuser but it’s a good quality system. Update: Day two my diffuser is even worse. The plate doesn’t seem attached and all the co2 is just leaking out the edge of the diffuser. Definitely a four star product because the diffuser is worthless. But that’s my only complaint. Solenoid runs cool, everything else works great.

This whole kits garbage. Every part except for the canister itself broke. One by one, it was first the solenoid, replaced it with the replacememt solenoid F zone sells, that also broke, and then so did the second one. Mind you, this is all under 2 months. Then the control valve broke and leaked a ton, so I had to replaced that. Then the bubble counter cracked on the bottom thread, again a huge leak. This thing wasn’t built to handle an attack from a butterfly. So in all I’ve bought the kit, 3 replacement solenoids, a new control valve (the part that screw into the top of the canister), and now I’m about to buy a replacement bubble counter. Garbage! The only thing that stands up is the canister itself and I bet that’s the only part F-zone outsourced. From experience, if you guys want a good solenoid, buy the Clscea one in my photos. And I tried replacing the seals on the control valve to stop the leak, to no avail. It literally shot baking soda all over everything for a good 7 minutes straight with no way to stop it. And a citric acid/baking soda mix is so difficult to clean if you let it dry, cleaning solutions don’t dissolve it. So I guess ill just live with the baking soda spray all over my aquarium cabinet. I hate this kit!

I have been running this setup on my 29 gallon heavily planted tank for about 6 weeks now. Ive had such a great experience with it that I ordered a 2nd setup for a 75 gallon tank that I am in the process of building. Pros: - High quality parts - Efficient CO2 generation. I have have a half a tank worth of pressure after 6 weeks - Easy to read gauges - All of my plants are growing like weeds. I've already had to trim them twice - The glassware that's included is very nice. - Plenty of length provided for the co2 hose Cons. - The instructions need work. Maybe it was me, but I had a hard time understanding them. I found a very helpful video on YouTube that clarified the math behind the citric acid & baking soda ratios. - The needle valve is very sensitive so you have to be careful to let the bubbles even out after touching the adjuster to get an accurate count. Other notes: - The setup is very tall when built. All the pieces mount vertically as well as the connection for the c02 house. I planned on having it in my cabinet but I didn't account for the bubble counter and hose being on top so it wouldn't fit. - The glass "U" connector is sized for a rimless tank. I had to cut a small notch in my tank to be able to use it. It is an easy modification to do but it something you need to consider. - A smart plug that allows for daily schedules makes controlling the system a breeze. I have it programmed to turn on at 8 am and shut off at 5pm. Running co2 at night is a waste as plants don't utilize CO2 without light. My lights are also on a controlled schedule as well but that's a different topic. Over all, this setup is a great way to get started with CO2 injection without having to drive around a find someone to fill CO2 canisters. It's possible it's more expensive to run long-term, but for me, being able to order citric acid and baking soda on Amazon that will last me an entire year vs lugging a tank to a paint all store is 100% worth it. I hope Fzone decides to make a 1 liter or even a half liter generator that I can use on my nano desktop tank.

Overall happy with my purchase and the price of the kit. The instructions included could be a bit clearer and seemed to skip over the installation of some of the parts, which I think is especially important for someone like me who is brand new to CO2 in aquariums. That said, assembly was easy enough. Needs a separate timer switch to utilize the solenoid valve, which seems to do a much better job of sealing the whole thing off than the valve on the canister itself anyway. Only other thing I'd note is the diffuser that came with my kit was cracked/chipped and not working correctly (still diffusing but not very efficiently, and with a pretty unpleasant hissing sound), but the seller was quick to send me a replacement which is working perfectly. Can't yet speak to how the whole kit will last over time as I've only been using it about a week now, but so far I'm quite happy and would recommend it (and the seller) based on the overall experience, my limited knowledge, and having shopped around a bit before buying.

I’ve been using the 5.5L FZONE CO₂ generator on my planted aquarium and have been very satisfied with it. The system holds pressure well, the solenoid works reliably with a timer, and the needle valve allows stable adjustment once dialed in. My plants responded extremely well, well enough that I eventually reduced CO₂ because growth became too aggressive. After a fresh refill, my pressure reached approximately 450 PSI. I contacted FZONE to verify that this was normal, and customer service responded within hours with a clear, detailed explanation confirming that it was expected and safe for this model. That level of support gave me considerable confidence in the product.

This 2.5L generator is a game-changer for planted tanks. The stainless steel cylinder feels solid and safe, the needle valve allows for precise bubble-count adjustments, and the included solenoid makes syncing your CO2 injection with your light cycle completely seamless. Tips for setup: Double Batch Capacity: Easily handles 400g citric acid, 400g baking soda, and 600ml water. The 45° Tilt: Keep the cylinder tilted at 45 degrees while pouring the water so the reaction doesn't start prematurely, clean the threads quickly, and screw the regulator on tightly. Output: Generates strong, steady pressure with zero leaks. Produces an ultra-fine mist and keeps CO2 levels perfectly stable without the hassle or recurring cost of commercial gas tank refills. Highly recommended!

Devo dire che all' inizio ero un po scettico sulla scelta di questo KIT fai da te, mi sono dovuto ricredere molto in fretta. Per cominciare il prezzo, rispetto ai classici impianti di CO2 costa molto meno, ti togli il problema delle bombole usa e getta che hanno un costo non indifferente senza contare che poi hai il problema dello smaltimento e per ultimo con una ricarica da 3€ ci faccio 3 mesi almeno. Intanto l' assemblaggio e la messa in opera una cosa facilissima, fai tutto in una mezzoretta ed è pronto all' uso, materiali veramente ottimi di prim'ordine, è 2 mesi che è in funzione e ho ancora più di mezza bombola disponibile. Però un problemino si è verificato, la valvola a spillo non si riusciva a calibrare, saltava da 15 a 30 bolle al minuto e non riuscivo veramente a calibrarla sulle 20 al minuto come io volevo, ho un acquarietto piccolo da 25 Litri. Decido di contattare direttamente FZone Europa lasciando fuori Amazon ma dialogando direttamente con loro. Impressionato dalla efficienza e attenzione ricevuta, mai successo di avere da una azienda una assistenza così attenta e personale, intanto le 3-4 mail scambiate ho interloquito sempre con la stessa persona ( Cheryl che ringrazio ancora per le attenzioni avute per il mio problema ) poi il tutto in lingua Italiana corrente ( senza traduttore Google ) invio un piccolo video per evidenziare il problema della valvola a spillo. Risultato? dopo 3 giorni avevo a casa non la valvola a spillo ma tutto il blocco del riduttore di pressione. Allibito e senza parole, non ci credevo, ora funziona tutto alla perfezione con le mie 20 bolle al minuto. Grazie FZone, il prossimo acquario che metterò su come cliente non mi perderete di sicuro. Io lo consiglio vivamente questo Kit per chi naturalmente non ha acquari esagerati. Prezzo conveniente, assistenza superlativa, costi di gestione molto contenuti senza sprechi.

I’ve been using this DIY CO₂ cylinder on my 50 gallon tank for about a year now, and it’s been consistently reliable. Setup was straightforward, and even if you’re new to planted tanks, it doesn’t feel overwhelming. The design is simple and intuitive, which makes day to day use pretty hassle free. One of the biggest advantages is how easy it is to refill. You don’t need any complicated tools or special skills, just a quick recharge and you’re good to go again. That makes it much more convenient compared to some pressurized systems. In terms of performance, it does exactly what you need. CO₂ output is steady enough to support healthy plant growth, and I haven’t faced any major issues over long term use. For beginners especially, this is a great starting point before moving on to more advanced setups. Overall, it’s a practical, easy to use solution that delivers solid results without overcomplicating things.

E da tre anni che uso questa bombola per la creazione di CO2 mi trovo benissimo, come con ogni prodotto di FZONE.👌🏽

Llevaba varios años usando el sistema de dos botellas de plástico y la verdad, si llego a conocer esto antes, antes lo uso. Es una maravilla se recarga fácilmente y sin perder tanto tiempo como con las botellas (mezclar independientemente ingrediente, apretar, agitar hasta que coja presión, etc....en fin una tortura). Con este sistema echas los tres ingredientes, bicarbonato, ácido cítrico y agua y a correr. En un cuarto de hora o menos ha cogido la presión suficiente. Una maravilla y sin el peligro de que te explote una botella (que ya me ha pasado). Estoy encantado, espero que me dure años.