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Availability:
Only 1 left in stock, order soon!
Arrives
Sep 27 – Oct 3
Features
- Helpful tool to grow lush and vibrant aquarium plants
- Simple and easy to install
- Suitable for aquariums up to 30 gallons
- Country Of Origin: Taiwan
Description
Since all planted aquariums lack CO2, it is extremely important that they are supplemented with it. In fact, 40 to 50% of a plant’s dry weight is composed of carbon. For optimal condition of aquarium plants, some CO2 supplementation is necessary. The Fluval Pressurized CO2 Kits come complete with all the necessary tools needed to grow lush and vibrant aquarium plants. This disposable cartridge system is ideal for small planted aquariums (up to 115 L/30 US gal). The kit includes : High-Quality Regulator Valve Support Base High-Quality Ceramic CO2 Diffuser which produces the finest of bubbles 2-in-1 Bubble Counter & Check Valve Hose.
Product Dimensions : 2.5 x 5.7 x 8.5 inches; 1 pounds
Manufacturer recommended age : 1 month and up
Item model number : 17554
Date First Available : August 12, 2017
Manufacturer : Rolf C. Hagen (USA) Corp.
Best Sellers Rank: #151,172 in Pet Supplies (See Top 100 in Pet Supplies) #2,536 in Aquarium Filter Accessories
#2,536 in Aquarium Filter Accessories:
Customer Reviews: 3.1 3.1 out of 5 stars (269)
Item Weight: 1 pounds
Manufacturer: Rolf C. Hagen (USA) Corp.
Item model number: 17554
Date First Available: August 12, 2017
Item Package Dimensions L x W x H: 8.46 x 5.71 x 2.68 inches
Item Dimensions LxWxH: 2.5 x 5.7 x 8.5 inches
Item Weight: 16 ounces
Brand Name: Fluval
Target Audience Keyword: fish
Model Name: 17554
Size: 3 Piece Set
Material: Ceramic
Number of Items: 1
Style: Classic
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Sep 27 – Oct 3
This item is non-returnable:
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
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Top Amazon Reviews
This system is not worth the price at all. I get having MTS and being so excited you'll justify any aquarium purchase. Fluval is great. This product is literally worthless. Actually, worse than useless. I'm familiar with pressurized CO2. I ran a GLA system controlled by a PH controller on my 75 gallon and 120 gallon for years. I know the things CO2 makes possible. I've also ran three connected 2-liters as DIY setups on tanks over the years and had to deal with algae caused by fluctuating CO2 levels. This is what I mean by worse than useless. When you try to dial in the desired drip rate, it's hard to tell the difference on the dial between completely off and on just a little. You try to turn it the littlest bit possible and a dump of gas. Try to adjust it back down and it's off, no bubbles. Plus, there's no solenoid so you have to figure out this adjustment daily to start the system. The only alternative is leaving it running and having an air pump on a timer so it runs when the lights are off. I started an ADA 4.6 gallon a month ago. I've used five 45g bottles so far. The last one was going after about eight hours. The tank has been without CO2 since. I ended up getting an Ista CO2 Aluminum Supply Set 1L (Premium) from Marine and Reef it was $200 bucks including a full 1 liter CO2 tank. (I think that's like 500g or so?) The tanks ship full. It includes a solenoid that you can plug into a timer. That's more than this silly set up but if a 45g tank last, at best a few days then this set is insanely expensive. If you're looking for something smaller than a 60 lb CO2 tank like I was please keep looking. You won't end up using this set for long and neither the system or refills can be returned.
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Reviewed in the United States on May 2, 2026 by Susan
I set this up on my new nano tank today and have had no issues so far. No leaks (I immersed each of the connections to check) and I'm getting fine bubbles from the diffuser. I read lots of the reviews here before I even ordered this and found some good tips. There are a lot of negative reviews, but my overall impression is that many people don't take the time to read the instructions and they set up this system before they have a good feel for what they're doing. As suggested by at least one reviewer, I used teflon tape on all the threaded connections, even on the bubble counter, which was probably overkill, but there's no downside. I made sure to install the bubble counter correctly, with the arrows indicating the direction of flow. I soaked the diffuser for a whole day before installation, as some reviewers suggested. I didn't have any trouble adjusting the regulator to get the bubble rate as I wanted it, and it has remained steady all day. The pressure gage is down about 200 psi after about eight hours of use, so I don't know how long the CO2 cartridge will last. We'll see... Lastly, I just wanted to add that this mini-sized kit is just perfect for a nano tank. A big gas bottle would have been in the way and unsightly, not to mention expensive. I also bought the tank on Amazon (Marineland Portrait Glass LED Aquarium Kit, 5 Gallons, Hidden Filtration). I hung the CO2 cartridge on the back and put the diffuser in the sump area, which also houses the pump and the heater (it came with the pump and I added a heater). There's no equipment in the main tank and the only part of the CO2 system visible from the front is the bubble counter on the side. The video shows fine CO2 bubbles being carried from the sump into the tank by the pump. Very aesthetically pleasing setup! Update: After using this system for two weeks, I changed my rating to two stars. The CO2 cartridges are lasting only three days each, which makes this cost-prohibitive to continue using. I’m so disappointed, because I love the overall design and size of this little kit. It fits perfectly and unobtrusively on my 5gal nano tank. Update 2: Before giving up, I took the system apart and added a lot more Teflon tape to all the connections, especially where the tubing connects to the bubble counter. Those connections seemed loose; the plastic nuts don't fit tightly enough to compress the tubing around the connectors, so I suspected I might have leaks there. I wrapped Teflon tape around the threads, connected the tubing, then wrapped more Teflon tape around the ends of the tubing and over the threads again, before screwing the nuts on. I also added more Teflon tape around the threads of the bubble counter itself, and also around the connection between the tubing and the regulator. And I replaced the gasket in the regulator (where the CO2 cartridge attaches). The kit came with two spares, so I figure why not. And of course I wrapped the threads of the CO2 cartridge with Teflon tape, as I had been doing. The result: I think my problems are solved! After three days of running the CO2 system about ten hours/day, one bubble per minute, the CO2 pressure has decreased almost imperceptibly. Yea! So I changed my rating back to 5 stars. As a side note, Fluval should really include a roll of Teflon tape with this kit and mention the importance of using it for leak prevention in the instructions! It might save a lot of frustration and disappointed buyers! Update 3: 9/22/24 – I'm consistently getting two weeks from each CO2 cartridge now, running the system ten hours/day at about one bubble/second. That puts the cost at about $5/week for CO2, which works for me!
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Reviewed in the United States on August 10, 2024 by Nancy K. Farlow
This thing is great for the price. I use this kit for about a month or so on a new aquarium setup to get my plants established and going before mainly dosing with fertilizer and occasionally using CO2. If I wanted to run CO2 automatically on a timer I'd end up buying something way more high end than this. I can understand the negative reviews because I gave it a shot and experienced most of the problems people came across. Those reviews are misguided however. You cannot rush the process as you're dealing with a little bit of science here. After I got the kit working the way I wanted it to, I ended up buying another kit for a second aquarium and that one works great as well. Follow the assembly instructions or setup videos as described, but here are few keys to success the directions don't do a great job of conveying: The water in the bubble counter should be about 70% full when filled with water and the top screwed on. Enough to cover the opening on the stem that goes into the cup. Turn the valve slowly. And by slow I mean 1/16 of an inch at a time. Let 5 seconds or so pass between each turn. This is super important for newer cartridges. As the cartridge runs lower on CO2 you can make your valve turns larger since there won't be as much pressure build up in the cartridge. As a side note I found the PSI gauge reader to not work well and isn't necessary anyway. When you begin to see the water slowly rise in the bubble counter you know its getting pressure. Bubbles will begin to come from the stem when its filled and built enough pressure. At this point you need to wait for pressure to build in the second hose and push through the diffuser. This can take a few minutes. I also noticed it can take a few days of usage before the diffuser breaks in and starts producing the finer bubbles you're looking for. They'll be a mix of large bubbles with smaller ones at first, just keep running it. Over time you may get small beads of water in the hose you can use to see the pressure moving through the hose as you turn the valve open to inject CO2. Just a useful visual aid, but you will get the hang of this kit over time if you use it everyday. Also get a CO2 drop checker as one is not included. You want to make sure you're not suffocating your livestock. I run these for 5-6 hours when the aquarium lights are on at 1-1.5 drops per second. I think I get 2-3 weeks usage out of a cartridge.
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Reviewed in the United States on February 28, 2025 by Joe N.
Trust the bad reviews. Hagen released a dud. The bubble counter/check valve is cheap and hard to seal, and the regulator is truly terrible. A fraction of a turn and it goes from no bubbles to 10 bps. I had to spend a half hour opening the tank, letting the sytem come to pressure, and trying to adjust until I finally got lucky and got it to a spot where it's doing 1 bubble every 3-4 seconds. There's no way I'm going to turn this off every night and spend 1/2 hour messing with it in the morning so the cartridge will last half the time. It's a shame because it's a neat little kit that takes up very little space and the diffuser works beautifully. Do yourself a favor and spend a little more money on a paintball CO2 setup. Update: Nearly killed my fish trying to adjust this wretched thing. One star. Do not buy.
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Reviewed in the United States on July 11, 2020 by E. Thompson
Fluval C02 kits are hands down the best way to get your feet wet in the aquarium hobby. These kits doesn't warrant all the negative reviews because of the buyers errors on reading simple instructions! I bit the bullet and purchased this item against all the negative reviews and it was well worth it, within 24 hours I have noticed a tremendous difference in my aquarium plants like I have never seen before. As a precaution I used a little Teflon plumbers tape on the threads of the cartridge,needle valve and bubble counter. No leaks what so ever, it's been almost a week with the cartridge it came with and I have more than 75% left to use. Doing roughly 1 to 2 bubbles per second for 8 hours on a 29 gallon tank. People having issues with leaks are stripping/cross threading the cartridge threads/bubble counter by the looks of it. Also the issue people are encountering with popping the c02 hose lines or diffuser is because they connected the hoses wrong on the bubble counter I'm sure of it. Needle valve is delicate to adjust like any other c02 regulator! 1 minor issue I have is .... The holder for the c02 cartridge is designed for rimless tanks, so be prepared for that. 1 tip I picked up from a reviewer is, to soaked the diffuser for 24 hours to get those micro c02 bubbles. If you have struggled with this kit, you should definitely not get into a larger c02 set up like 5LB c02 tank until you have mastered and learned from this kit.
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Reviewed in the United States on November 13, 2023 by B.E.N.Y.
The product is pretty good. I modified the plastic holder for the CO2 because it wouldn't go over the side of my rimmed tank. I just used a miter saw to create a wider notch. Tip: at night, detach the hose from the bubble counter to the diffuser so it doesn't fill with water and pop when you turn the CO2 open the next day. I suppose it's a pain to connect and disconnect the hose every day, but this system is cheap enough it who cares? Disconnecting your hose at night will spare you a lot of tubing pops, and I've noticed that's a common complaint. Lastly, DON'T WASTE YPUR TIME on the diffuser. Go buy a better one. The packaging said it may take a few days to create the fine mist bubbles....it never really did. There were soooooome fine mist bubbles after a couple days, but they it'd just go back to be one large bubble when I adjusted the bubble counter, and that is a total waste of CO2. Forget it, don't waste your time with that cheap plastic thing. I am awaiting the delivery of a glass diffuser as we speak.
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Reviewed in the United States on June 24, 2024 by Amazon Customer
Straight out of the package leaking from the bubble counter. Not to mention the regulator is crap. It’s either all or nothing, I could not get it set to a certain amount of bubbles per second. The diffuser was also junk and let huge bubbles out rather than diffusing them, and yes I pre soaked the diffuser. Everything in the kit is flimsy and not worth your money. This lasted a whopping 10 minutes on my tanks before throwing back into the box it came out of.
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Reviewed in the United States on November 8, 2023 by Nathan Metayer
A lot of negative reviews for this product, but it works absolutely perfect for me! From what I’ve been seeing and reading, it appears a lot of people buy this as a beginner CO2 kit, which it absolutely is, but have not fully followed the instructions. I followed the instructions to the “T” and also soaked the diffuser in tank water for a few hours before turning the kit on. Works beautifully! Small micro bubbles are diffusing throughout the tank and I am already seeing a positive effect after just a few days with my plants. CO2 is very tricky with a fish tank. Unless it’s done perfectly, I can see why a lot of people would have issues. However, this product is great and a wonderful way to start introducing CO2 tip tank.
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Reviewed in the United States on November 27, 2025 by Nancy S. Lynch