FZONE 2.5L Aquarium CO2 Generator System Carbon Dioxide Reactor Kit DIY Co2 Kit with Regulator And Needle Valve For Aquatic Tank (with solenoid)

After carrying out a lot of research I decided this system would be the best bang for bucks system for my 120L system.I've been running the generator for 3 months now and I'm really impressed with it. It was easy to set up and the raw ingredients are cheap and easily purchased from Amazon.The powders are added and then the water is added very slowly with the bottle at a 45 degree angle. pouring it slowly slows down the chemical reaction and stops you wasting gas as you screw the regulator on to the bottle.I was getting 2 weeks of CO2 from one charge and when I added a CO2 reactor that figure went up to almost 4 weeks. 4 weeks of CO2 from 200g of acetic and 260g of Bi Carbonate is in my opinion amazing.The regulator is easy to adjust and the solenoid valve works as it should.The kit itself contains everything you need, except the raw materials and a drop checker. These can be picked up cheaply from Amazon.CO2 has made a big difference to my plants and algae growth is virtually zero now.This kit has been the best piece of kit I have bought for my aquarium in a long time. If you want to add CO2 to your system this is a great straight out of the box solution.

This is a fantastic purchase if you’re looking to add CO2 to your aquarium. I explored a few different options beforehand, including using a fire extinguisher setup that could be swapped at my local fish shop, as well as refillable canisters, but honestly nothing beats the convenience of being able to generate your own CO2 at home with this system.In some ways, it’s actually more efficient than swapping canisters too. When it’s time to regenerate the CO2, you can simply do it overnight while your CO2 system would normally be off anyway. With refillable canisters, you usually end up needing to swap them during the day, meaning the aquarium can be without CO2 for a period of time.One tip I’d give is to use ice instead of water when setting it up. That slows the reaction down for a few hours, because if you add water straight away the reaction starts immediately and you can lose a bit of CO2 while screwing the canister back together. Using ice really helps with that.Overall though, I’m extremely happy with it. My aquarium plants are thriving and the whole tank looks so much healthier and vibrant since using this system.

This was the first time I have added CO2 to my planted tank ,thought long and hard before deciding to go for Fzone 4lt CO2 reactor also watched a lot of you tube videos about CO2 reactors,some good videos of the unboxing and set up of this set .This came packaged well with everything needed for set up This was quite easy to set up for a beginner, instructions could be better but are ample ,canister looks well and the regulator good, loads of CO2 tubing and suction cups also ubend for attaching to tank if required,diffuser supplied as well, cannot comment on diffuser as bought different one due to some of the comments on other reviews ,it also comes with solenoid for for running a CO2 schedule you need to buy your own smart plug or timer switch for this ,you also have to buy your own ingredients for making CO2 ( baking soda and citric acid ) There also seems to be issues with the amounts of each to be added ,some good videos on YouTube regarding this. I have now had this set up and running for more than one week all is working well pressure is good solenoid is working well ,only running for 7hrs a day on a 168 ltr tank ,running at 2 bps and have not had any problems at all I would recommend this for someone thinking about using CO2 in their planted tank I think this is good value for the money will update this review at a later date regarding how long cannister lasted , PS plants are loving CO2 and growing well . You will need to buy your own CO2 drop checker and fluid and this is safest way to monitor CO2 amount.

This is the second FZONE system I have ordered not because the first one was faulty but a second one gives me the of having a pressured system ready to swap immediately the working tank empties. The system is easy to install and use on a daily basis and is easy to clean after each recharge. There is no smell from the unit and appears to be of a high quality that will last. It has been connected to my 250l tank for four months now with no issues. The solenoid is controlled by a PH controller and, with the use of a smart plug switches CO2 injection off at night. This is important as the plants do not use CO2 at night so there is a chance of gassing the fish if it were to run with the lights off.Plant growth is certainly improved and I am now able to grow some stunning specimens of Red Tiger Lilies with some off shoots achieving a height of 18 inches in around a week. The biggest effect is on invitro plants that can double in size in a 24 hour period.

This co2 generator is so simple to use. The instructions could be better but other than that it's great.If it helps, i try to remember this formula:citric Acid = ABicarbonate soda = BNotice how the A and the B in the names are the same as the A and B on the bottle? i hope you do... and that's how i remember the instructions of which powder goes in first.So i've had this generator running now for just over 4 weeks, running approx. 4 bubbles per second on a large aquarium. I am quite happy with the results. I don't wish to deal with getting co2 refills, tho i may still go down that path in the future.I've now purchased a second one of these 4L co2 generators to add to my setup.One thing i will add is that i used black airline tubing which is thicker than the tubing provided and does a much better job at supplying co2 to my tank.The only issue i have with the kit is the funnel and beaker which you get is too small to use with the 4L generator. The funnel takes a long time to get the bicarb into the cylinder so you want to use a larger funnel with a larger hole . Also the beaker only holds around 300 grams product when you need to measure out 600 grams. It's just not ideal and feels like somebody cheaped out tbh. Such a tiny let down on a great product.I will update my review in a month or two on how things are going. I can only imagine that i'm going to be just as happy in my next update - tho still upset at having to hunt down a larger funnel.maybe i'll have purchased a 3rd kit by then lol i think i do need a third... omg fish tanks right? ;) haha haha

I’ve purchased the FZONE 2.5L Aquarium CO₂ Generator System (with solenoid) three times now, and unfortunately each unit has had some kind of issue.When the system is running properly, it does its job well. It produces stable CO₂, the regulator and needle valve allow decent control, and it’s a convenient DIY-style setup for planted tanks without going full pressurized cylinder. For the price, it’s an attractive option.However, reliability has been inconsistent. I’ve experienced failures with different components across the units, which is frustrating — especially when running CO₂ on a planted tank where stability is important.Overall, it’s functional and affordable, but quality control could definitely be improved. I’d rate it 3/5 — good concept, just needs better durability.

I was using a different type of co2 kit from a well known brand that takes canisters and it was so expensive and time consuming.This kit is amazing, it comes with a solenoid so I have it set up on a timer to turn on and off automatically. I have been using this one for a month now and it's paid for its self because of the amount of canisters I would of had to buy in that time for the old co2 system I was using. Its simple to set up, I used a video online with a detailed unboxing/set up guide and it was done in around 15-20 minutes. You need to buy the sodium bicarbonate and citric acid which is cheap enough especially if you buy a larger pot of each. I have a 190l tank and this is on for 8 hours per day at 2 bubbles per second and it's still got around a third left so I expect this to last about 7-8 weeks every time I fill it for my tank. Highly recommend.

Very disappointed with this after the regulator failed 11 months in and despite promises from fzone to replace the parts , I still have not received them and despite several contacts I have been without a working c02 setup since Dec 2025, I have had to bite the bullet and purchase from another company the full setup again, shame on you Fzone. Very disgruntled customer

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.

This kit has been an excellent addition to my aquarium setup. The setup process was easy, and the build quality is solid and durable. The regulator works smoothly, offering precise control over CO₂ output. The system maintains stable pressure consistently, which has helped improve overall aquatic plant growth. Overall, this is a great value for beginners looking for an efficient CO₂ system.

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.

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.

今まではボンベを買って月に一本のペースで交換してましたが今回初めの化学式ボンベを購入しました重曹とクエン酸(別売り)があれば水を入れて　その日の内に添加可能で　いい買い物をしました。逆流防止弁とタイマーを別で購入して設置したので　ライト　エアレーション　co2 のオン　オフが自動化したので　朝のエサやりと週一の水換えのみなので　すごく楽になりました！設置初日なので星4にしときます！