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Alternatives to a CO2 injection

InNi2010

Member
Joined
6 Feb 2022
Messages
55
Location
Good Ol' Sutton
I want to stay as budget friendly as possible. I don't want to rip a hole into my pocket and let my money spill out into an expensive kit so I am looking for any alternatives to a CO2 injection. My plant selection is going to be ones from Tropicas easy range. I've looked into liquid carbon dubbed as an alternative. but after watching some videos on YT it seems like it's only just an 'algae-cide'. People say good water flow introduces a bit of CO2 from the air into the tank. So far everyone (on YouTube) say there isn't an alternative and you should just stick to the classic injection. What do you guys think 💬

Many diy kits like yeast powered ones only last for a fortnight. Also they are not controllable so I can't turn them off at night and thus my fish die so I kinda cut out the option
 
Yeah there isn’t really an alternative to Co2 injection.

I suppose the alternative really, is that you just run a low tech system. There are plenty of lovely tanks out there that are run this way. And plenty of people on this forum doing it.

My advice. Head to the journals section, find a tank that is similar in size to yours and interests you. Then emulate it.


Co2 doesn’t have to be expensive though, the initial cost for a decent regulator is high, but you can buy second hand and they last as long as you need them.
 
Many diy kits like yeast powered ones only last for a fortnight. Also they are not controllable so I can't turn them off at night and thus my fish die so I kinda cut out the option
You can turn them on and off if you use a water pump for the diffusion. In my smaller tanks I use home-made internal CO2 reactors with a small dedicated pump and just turn it off at night. Excess gas escapes at night through the pump.

The reactor is a bit unsightly, but you could just connect your kit to a simple circulation pump, either at the suction so it passes through the blades,or at the venturi at the outlet.

But the truth is that your fish won't die from having CO2 on at night. Even during the day, only a small fraction of the CO2 is absorbed by the plants, most of it diffuses to the atmosphere. It will be almost the same at night. The important part is to have enough surface agitation to assure sufficient gas exchange, but that goes for the daytime period as well, not only for the night.

Finally, a low tech system is perfectly viable. It is just a different rhythm.
 
The initial outlay can be a little expensive, but you can pick up quality preloved regs and other CO2 equipment relatively cheap on our sale/swap/wanted thread.

Also, it's easy to use fire extinguishers as a cheap source of CO2 (those past their sell by date are very cheap and usually still very safe), and inject just enough to turn the drop checker green rather than lime green.

That way an extinguisher will go further and the plants will still benefit. The tank will tick over a little slower, giving you a slow burner, and be less demanding in terms of maintenance and water changes.

Low-energy and non C02 methods are also a viable alternative, and you're right the key is good surface water movement to aid gas exchange and max CO2 in low-energy tanks. Either way stick with "easy" plants from the Tropica list ;)
 
The initial outlay is a little expensive, but you can use a fire extinguisher as a CO2 source and inject just enough to turn the drop checker green rather than lime green it will last a while longer and your plants will still benefit. And the tank will tick over a little slower, meaning less maintenance; a slow burner. Low-energy is also a viable alternative, and you're right the key is good surface water movement to aid gas exchange and max CO@ in low-energy tanks.
That's the way i've just set up last weekend, a 5kg fire extinguisher cost £30 plus the Fzone co2 kit £109, twinstar diffuser and tubing and test kit, on a 20 gallon plus tank iam running 1 bubble per second, it only took the next day for the colour test to turn lime green and the ph to drop to 6.5, total cost bout £180 but at 1bps i expect a 5kg cannister to last some time then only need to replace that next time around.
 
Plant choice definitely makes a big difference too so if you're going for ones from the Tropica easy range, you can emulate the lush growth to a degree by choosing some faster growing stems rather than just slower growing rhizomes/rosettes. Design also helps; some styles call for CO2 more than others. I prefer nature style personally so I don't run CO2 in any of my tanks as it's not necessary. If I wanted Iwagumi or Dutch style, I'd be more likely to need injection. My tanks would obviously grow faster if I injected, but I'm happy with the tortoise approach!
As far as alternatives to CO2, I think that's been covered above; there is either CO2 or low tech but there are varying degrees of cost/complication to a CO2 set up so it doesn't have to be an all singing, all dancing, 2 months wages kind of set up.
 
Would this work?
Anything else I would need to add?
All those small diy type set ups are totally uneconomical, you'd be paying £5.49 for a 12g can refill v £30 for my 5kg fire extinguisher can...you can see the maths

i bought this and added to it diffuser, tubing and co2 in tank test

https://www.amazon.co.uk/FZONE-Regulator-Adjustable-Integrated-Precision/dp/B0B1VK47Z9/ref=sr_1_6?crid=L07A0CQK31Z0&keywords=fzone%2Baquarium%2Bco2%2Bregulator%2Bdc%2Bsolenoid&qid=1671567734&s=pet-supplies&sprefix=fzone%2Cpets%2C81&sr=1-6&th=1
 
Yes for sure, it’s old skool, but will work fine. Tropica do something similar. Available at Pets @Home.


But they’ll both work out more expensive in the long run.
 
Here's my recent (past week) experience with cheap CO2 setup, total cost £74.45.

CO2 source
--------------
1. Find a fire protection company in your local town, either google maps and/or check this website: The British Fire Consortium - Members
2. Call the up and ask if they have any expired CO2 Fire Extinguishers you can take off their hands - What I learned is that fire extinguishers have an expiry date beyond which they cannot be used for fire fighting and have only scrap value
3. I managed to find a local fire equipment supplier (not willing to be named, otherwise I would) who was also an ex-aquarist (handy) and he provided me with 2x full expired 2kg CO2 (so 5KG gross weight including cylinder) for £5 each.
4. He said to just bring the cylinder back once empty and he'd then scrap it and I could take another one off his hands for a fiver each time.

CO2 regulator etc.
----------
1. Mufan CO2 Regulator from Ebay £28.99 Fish Tank 2 Gauge CO2 Pressure Regulator Bubble Counter Solenoid Valve Aquarium | eBay. Comes with a needle value and bubble counter. Mine had a dodgy 3 pin UK plug, where if you wiggled the cable the power would toggle solenoid on/off, so I just cut off the supplied plug and replaced with a new one, no problems since. No idea how this will hold up over time, but at this price, who cares.
2. CO2 drop checker and solution from CO2 Supermarket £13.99 (via Ebay)
3. Aquario Neo CO2 diffuser (small) £12.99 from Horizon Aquatics
4. CO2 resistant tubing 3m from Horizon Aquatics £5.49
5. H-Series Clear Check (non return) valve from Horizon Aquatics £2.99
6. WiFi smart home plugs x2 from Ebay to control timer for Lights and CO2 Solenoid via Smart Life (free) smartphone app 20A Smart WIFI UK-Plug Socket With Power Monitor Wort with TUYA / Smart Life APP | eBay £18.70 . I actually bought mine a few years ago in bulk from China and were about £5.99 each, price gone up since and if you want onshore (quick supply) then you have to pay a premium.

So my entire setup including spare CO2 cylinder cost £74.45 (or £93.15 if you include the wifi timer plugs).

Oh...and you'll have to splash out on a cable tie to keep the handle/valve on the extinguisher open - might be a deal breaker this one ;)

I'll post a link to a video about this setup shortly if anybody is interested.

Hope this helps!
IMG_3868.PNG
 
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Out of curiosity, how are you guys getting these "expired" fire extinguishers refilled? No regs in UK?
In the US, our tanks need to be tested+inspected and stamped every few years, otherwise no one will re-fill them...
-99
 
Out of curiosity, how are you guys getting these "expired" fire extinguishers refilled? No regs in UK?
In the US, our tanks need to be tested+inspected and stamped every few years, otherwise no one will re-fill them...
-99
I don’t think they get them refilled. They’re handed back empty (the cylinder is recycled) and exchanged for a full one.
The whole scenario is based off fire extinguishers that are no longer fit for purpose, so they don’t have current stamps etc….
 
im not sure why people say you cant turn off a diy yeast and sugar co2 set up because you can control it with a solinoid and a timer in the same 2 bottle setup used for citric acid and bicarb. You just need to use new 2ltr soda bottles and mix the sugar solution with gelatin to slow the reaction. The second bottle is just water. i did this for several months after a citric acid and bicarb setup blew up in the middle of the night. presure on the yeast and sugar setup would never get anywhere close to the same as the acid setup even after 10 hours with the valve closed.
 
Understood, thanks.
I'm surprised that you are able to obtain them like that at all.
Out of date extinguishers are usually still safe, just not legal for extinguishing fires.
In the UK, at least, they can still be used for home brewing and planted aquariums etc.
 
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