# Simple DIY CO2 Reactor



## Ed Seeley (2 Apr 2008)

I needed a CO2 reactor for my 180 l tank and so, as I usually do, I went down the DIY route.  I had a gravel cleaner (now unused), a spare top from it's predecessor, an airline connector, some Bioballs (Pond biological filter media) and some spare 12/16 Ehiem tubing and realised these could make a good reactor






Basically the CO2 is fed into the tubing just above the gravel cleaner reactor.





The water flows down into the reactor where as many bioballs as can fit in were placed to mix up the water flow.  





All the joints on the gravel cleaner and the point where the airline connector goes in were silicone sealed to prevent leaks.

Since making the unit I found that the pipe going into flexible tubing flexed and after a few months leaked very slightly.  So I took the shepherds crook from my old filter and drilled a small hole.  I then fitted the airline connector there and Araldited it into place.  I also found it was best to fit a check valve near the reactor and another one near the regulator as water crept back down the CO2 tubing.  The extra check valve solved this.

This set-up ran for nearly a year before I moved the CO2 to my new tank (I will be adding CO2 back to this tank once a new regulator arrives).  

Interestingly my 180l tank upstairs needed just over 1bps to maintain 30ppm CO2 but on my new tank the same CO2 kit but with a glass diffuser needs nearly 3bps (in the same bubble counter) to give the same result!  It may be because of the tank, but I think that the effectiveness of a reactor can't be beaten!


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## Themuleous (3 Apr 2008)

Nice write up Ed, it really is simple hey?  Maybe I should try some of these myself.

Sam


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## Steve Smith (3 Apr 2008)

I'm headed down the local B&Q asap


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## Ed Seeley (3 Apr 2008)

DevUK said:
			
		

> I'm headed down the local B&Q asap



All of that kit is from an aquatic shop not B&Q!  

If you want to go with stuff from B&Q then you really need PVC pipe and it gets a little more complex than this, but not too bad.  Yhe problem, as you hinted in the other thread is really the hosetails.  The easiest way I reckon to make a reactor might actually be with pond stuff.  Get 1.5" Solvent weld hosetails and a length of 1.5" waste pipe.  Make sure they fit (you may need some reducer rings but a good pond plumbing supplier should have these) and then glue them all together and a simple black reactor.  Unfortunately clear pipe is way more expensive than black.


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## LondonDragon (3 Apr 2008)

Looks great, and its a simple solution for a reactor, not sure if I would do it though, the thought of flooding my living room is not good! Specially after my other tank burst a few months back, wasn't fun sweeping 100l of water at 11pm!!


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## Ed Seeley (4 Apr 2008)

LondonDragon said:
			
		

> Looks great, and its a simple solution for a reactor, not sure if I would do it though, the thought of flooding my living room is not good! Specially after my other tank burst a few months back, wasn't fun sweeping 100l of water at 11pm!!



It all needs siliconing together to make sure this doesn't happen!  You could always put hoseclips on the pipes too to secure them to the hosing even more securely.


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## LondonDragon (1 May 2008)

Ed, what size Bioballs did you use, does it matter? 
Been checking around and most only do large quantities.
Seen them on ebay for Â£5 inc postage for 50! which is way too many.


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## Ed Seeley (1 May 2008)

LondonDragon said:
			
		

> Ed, what size Bioballs did you use, does it matter?
> Been checking around and most only do large quantities.
> Seen them on ebay for Â£5 inc postage for 50! which is way too many.



I used some pond ones as I have the rest of the two bags in my trickle filter on the pond!  However to be honest I think you could do without them as lots of designs on the American sites don't use them.  Any cheap plastic media would do the job if you did want to use them.


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## LondonDragon (1 May 2008)

Ed Seeley said:
			
		

> I used some pond ones as I have the rest of the two bags in my trickle filter on the pond!  However to be honest I think you could do without them as lots of designs on the American sites don't use them.  Any cheap plastic media would do the job if you did want to use them.



Thanks Ed, I will think about it then, if I have any questions I will bug you some more


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## milla (1 May 2008)

As Ed said, you can do without.  The idea of the balls is that the bubbles collide with the balls and break them into smaller  bubbles so that they diffuse quicker.
An alternative is plastic netting as used in the german reactors, a cheap alternative is the plastic pan scrubbers you can get at any supermarket for pennies.


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