Aquarium CO2 Reactor 12/16mm

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GLA Aquarium CO2 Reactor -12/16mm
GLA Aquarium CO2 Reactor -12/16mm
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External CO2 reactor for high efficiency CO2 dissolution by internal whirlpool waterflow, allowing 100% CO2 dissolution in aquarium water. Made of highest quality food grade materials.

  • mount outside aquarium tank, inline within outflow tubing of canister filter

  • fits tubing size 12/16mm ID/OD (inside diameter /outside diameter)
  • height: 15 inches (375mm)
  • diameter: 4.5 inches (116mm)
  • volume: 2.5 liters

Customer Reviews

12 reviews

  • 5

    100% Co2 saturation.

    Posted by Mike L. on 21st Sep 2021

    Excellent reactor, dissolves all co2. I like how large it is compared to the dinky one I had before lol.

  • 5

    Co2 reactor that works.

    Posted by Eli Manning on 15th Sep 2021

    No more mist in the aquarium upstairs so family can enjoy it besides me. My little one always asked why it was so bubbly so I decided to give this a go. I did not care much for the check valve included so I ordered a GLA super valve just in case. Its a large reactor so it has no chance of co2 bubbles escaping. When I look at it I dont even think thats remotely possible due to the design. Great price and happy with the reactor.

  • 5

    Beautiful planted aquarium co2 reactor.

    Posted by Sean Wilcox on 9th Sep 2021

    Exactly what I needed from a reactor. Large in size and looks great under the tank. It was a seamless pair with the GLA DS-1 Co2 system. Great service from GLA.

  • 5

    Fantastic aquarium co2 supplies from GLA.

    Posted by John Warren on 6th Sep 2021

    Been a customer with GLA since 2007, its been a long journey watching these guys develop into greatness. I came back to GLA to reup on some basic supplies and decided to give this reactor a go. I really like it. The water is crystal clear, had no idea how foggy my GLA diffusers were making the tank so cloudy. Those Atomic co2 diffusers pack a punch! This reactor works fantastic!

  • 5

    Perfect reactor for my 2217 filter

    Posted by Mike Morgan on 3rd Sep 2021

    Thanks to this reactor my tank is nice and clear. It takes up more room than a diffuser but I prefer this method vs the ceramic diffuser method. Easy setup and shipping was fast.

  • 5

    Perfect working co2 reactor.

    Posted by Isaac L. on 28th Aug 2021

    It works just as it should. Co2 is 100% dissolved. Connections were easy and straight forward. Delivery was speedy, considering the pandemic.

  • 5

    Works really well.

    Posted by Aaron W. on 8th Feb 2021

    I decided to go with a reactor for my tank just as a test to see if I would like it. I actually love it. No more mist in the tank and all my co2 is 1005 saturated. Im going to get the 16/22mm version for my Oase filter tomorrow!

  • 5

    Great reactor

    Posted by Levi on 17th Apr 2020

    I opted to buy this reactor after I built one myself months ago. Although mine worked great, it required an external pump to power it, and it was massive. This GLA reactor is hooked to my eheim 2217, and runs like a champ. Came with everything needed, setup was very easy, and within 2 days, I had my co2 back up and tuned in. For reference, I have a 75 gallon tank, with high light, and pairing this with the GLA Gro-1, I think my setup will be bulletproof for months to come. GLA is making big waves in the industry.

  • 5

    Works amazingly well.

    Posted by Greg Minnor on 18th Feb 2020

    Im using this co2 reactor on my 75g tank and very pleased with its performance. Installation was a breeze with easy to follow diagram. Fits perfect next to my oase canister filter even though from what my friends say this reactor is of impressive size. It does have some volume you to it and I love the clear housing because you can see everything happening. What I like most with this co2 reactor is it requires no internal media,no bypass and no electric pumps. Its design alone gets all the work done with a cool whirlpool motion inside. Even my friends envy my GLA co2 reactor. :)

  • 5

    Works well

    Posted by Kaveh Maguire on 4th Feb 2020

    Great product if you are tired of that fizzy soda look in your aquariums from inline diffusers or in tank diffusers. Much nicer than the DIY one I was using before. I bought one for my 120 and loved it so much that I got an another one for my 100 gallon. My only complaint (and this really goes for all GLA products I have bought) is I feel like some documentation is really in order. It comes with an IKEA type drawing which is fine but it really could do with a manual. My advice when using this or other reactors is if you are using an inline heater as well don't use both a heater and reactor on one canister filter. Also this reactor will be very noisy while filling it is filling with water (and it fills up fairly slowly) but in my case by the next day it had filled and was quiet. Don't try to bypass this by filling up the reactor with water before you set it up. I thought I was being slick and tried this with my second one and my filter would not run properly. The reactor needs to be empty when you set it all up.

  • 5

    The Best Co2 reactor

    Posted by Ken Brill on 3rd Feb 2020

    This has to be the absolute best co2 reactor. The photo doe snot do it any justice, but you can visualize by scoping out its dimensions. I was already aware of how large of diameter it was when I was reviewing the specs of the co2 reactor but its when you get it home you quickly realize how awesome it is. The whirlpool action is totally awesome, comes with a check valve and extra bits for future use. I have some old reactors I have used that I purchased elsewhere but was not a fan of ball valves and the dinky 2" diameter. This co2 reactor is total beat mode activated. 4.5" diameter! Love it!

  • 5

    Absolute best co2 reactor

    Posted by Dave Chang on 27th Jan 2020

    This reactor has been a blessing to me. I tried other reactors and inline diffusers and nothing really worked well for my big tank(180g). This reactor is well built and is large enough to handle my 180g with ease. It worked so well I got another unit after running this one for a month. I now have 2 reactors, one on my 180 and one on my 60-P. I will never use anything else in the future. It comes with a check valve and easy to follow diagram. Its by far the largest co2 reactor I have ever seen and used. Most all other reactors are quite small, this GLA co2 reactor is all business. This has to be the best aquarium co2 reactor on the market.

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