HAGEN FL MINI PRESSURIZED 20G CO2 KIT

Nice little co2 system. Perfect for a nano tank. Easy to use, works great, fast shipping and well packaged. Great value for the money.

I ordered three of these sets on sale here for under $13 a pop, and so far, I think that they work really well for what they are at an extraordinary price. This is not a pressurized system, it’s passive C02. A bubble counter and different diffuser won’t work well with it. Just fill the diffuser with aquarium water when you put it in, keep the provided diffuser low in your tank, fill the chambers once or twice a day when you have plenty of light and let the pressure of the water do its work dispersing it. Only attach one chamber for a five gallon, both chambers for anything up to a 15 gallon tank. No, the diffuser is not elegant, but I can already tell that my plants are responding after a couple of days of use. I’m guessing that the diffuser will soon be well-covered by plant growth, so I’m not concerned with its lack of beauty. In addition, I like the safety of this system. It’s a safe system of dispersal that won’t leave your fish gasping for oxygen. That makes it perfect for beginners who are willing to learn to use it as intended. I do recommend buying generic threaded replacement C02 cartridges for cheaper than what Fluval charges for their brand, but those are available all over Amazon. All in all, so far, so good.

I purchased the Fluval Mini Pressurized CO2 Kit several months ago. It is a manual CO2 delivery system, so you will need to turn the CO2 regulator on and off each day. The regulator is a surprisingly low quality and it takes some time to get it "just right" (i.e. ~1 bubble per second) before you can leave it alone. This is why I gave it a one star rating for ease of use. After about 9 weeks of using this system, the regulator broke and I wasted 3 or 4 CO2 cartridges as a result. I called Fluval and they were very nice and sent me a replacement. However, it was the larger 45g system. This system was even more difficult to regulate the CO2. Read reviews on it and you will see what I mean. At the end of the day, I wound up purchasing a CO generator with a solenoid. This is a much better system as 1. the regulator is much easier to control and 2. the solenoid allows you to use a timer (you need to provide the timer) to control when and for how long the CO2 is on. At the end of the day the inconvenience of having to turn on the CO2, work several minutes to get it to the desired bubble count, and perhaps most importantly, the cost of the CO2 cartridges, makes this a low value. Will it work? Yes. But you need to watch it carefully and you will spend quite a bit on CO2 cartridges over the life of this system. In fact, it's a safe bet you will spend more overall on a system like this versus a CO2 generator. Yes, the up front costs of the CO2 generator are higher, but then you will only need to buy citric acid and baking soda every so often versus a CO2 cartridge most likely at 1 per week or week and a half at best,

Background on the context of this review. This unit was purchased for a highly planted, highly stocked, high light (~3.4w/per gallon) 10 gallon nano-tank setup. I had previously been using a DIY method and Excel dosing for my Co2 needs, but wanted to make the plunge into the injected aquarium setups.Ok, so first off, the diffuser this thing comes with is huge. The stock diffuser is at least 6 inches tall and about 2 inches wide -- space that I do not have available in my 10 gallon. If you are using this for a nano setup, go ahead and purchase the Fluval Bubble Counter and Ceramic Diffuser (you will also need Co2 tubing). Just an FYI, the regulator (or place where the Co2 cartridge screws in) would connect first the Bubble Counter (outside the tank), then the output from the Bubble Counter is connected to the ceramic diffuser in the tank) While you free up more space with the ceramic diffuser, you will need a bubble counter to monitor how much Co2 you are releasing. All together, you should be able to get this whole setup, plus six extra Co2 cartridges for ~$75.The main thing you are buying with this unit then is the regulator valve. The valve accepts threaded cartridges (like other reviews on Amazon, you can buy the 16g Threaded Replacement Cartridges cheaper than the 20g Fluval branded ones -- note though that the 16g do not fit into the holder as they are too short. I used a water bottle cap to jam into the holder to keep the top of the cartridge above the lip of the holder) and comes with (1) one 20g unit. Like other reviews on here, the regulator valve is sensitive, so trying to dial in the exact amount of pressure needed can be tricky. But keep in mind, this is a $20 setup and I think it is solid for the cost. The 16g cartridges seem to last from 2-4 weeks depending on how much/how often you are dosing.A quick note on dosing, because this setup is manual, it can be tricky to dose. If you use the included Co2 diffuser, it is not so tricky because you simply fill the containers and wait for the gas to dissipate before refilling. However, if you are using the ceramic diffuser, it is impossible to tell how much Co2 saturation you have in the water at any given moment without purchasing a drop-checker. Ideally you want ~30ppm of Co2 gas if you have a drop checker to do it. I decided not to buy one as it is yet another thing to purchase, plus it looks ugly hanging on the glass of the tank. If you are using the ceramic diffuser and have a 10 gallon tank with med/soft water, I would recommend dosing twice a day (once in the morning, once in the late evening) at around 1-2 bubbles per second for around 20-30 mins. I have had great success with this schedule and have not had big swings in ph or adversely affected the fish. One con of this unit is that it is manual, and is not an electronic solenoid -- and therefore requires you manually dose the tank. This can be hard if you are going to work/school for 8+ hours and will not be home. But the unit is substantially cheaper than professional electronic solenoid units, so there is that.Overall, this is a great unit for someone looking to get into the Co2 injected planted aquarium realm without breaking the bank. If you are going to use the ceramic diffusion method and will not be able to dose your tanks on a consistent schedule due to work, etc., I would recommend continuing to dose excel at low levels to maintain optimal growth and stave off algae. Also get some Aquatek Co2 tubing. You will prevent any leaks and make sure you are using the small tanks efficiently.