# C02 diffuser for a 3 gallon tank



## Wasserpest (Jun 12, 2003)

I used to make diffusors for CO2 like that... find a branch of a suitable tree (I used Linden tree _Tilia_ for that) cut off the outer layer (bark), let it dry a couple of days, cut it to about 1/2 in length, and stick it into an airline. Position this as low as possible (close to the substrate) in your tank. Once the pressure builds up, you get very fine CO2 pearls which mostly dissolve on their way to the surface.
There can be quite some pressure in this system, and the wooden diffusors need to be replaced once in a while. But nothing beats the size of them.

On the other hand, if you do use a reactor, you can just use any diffuser or let the bubbles bubble into the reactor. I imagine it can be easily overdone in a tiny "tank" like this one.


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## ritt (Sep 10, 2003)

I didn't realize one of these diy c02 systems using a soda bottle produced that much pressure. Could I possibly use a fine air stone. Do these systems create a constant c02 pressure that dose not change much.


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## Wasserpest (Jun 12, 2003)

They create enough pressure to burst the bottle, covering an entire room in a slimy stinky layer of sugar and yeast. If you happen to close them with an unmodified cap, that is. Yes, you can take a fine air stone as well.

The rate of CO2 production depends a little on the mix, the water, the yeast etc, but I would say it takes about a day or two to ramp up to full, more or less constant production, and then after 7 to 21 days it peters out. 

The CO2 output goes down with lower temps and up with higher temps. This is mostly a good thing, because if it is colder at night the output is decreased, and at night the CO2 isn't used. I heard of ppl trying to control CO2 production by heating the bottles with ballasts or letting them stand in water with controlled temperature.


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## ritt (Sep 10, 2003)

does any one think i might over dose my tank by using a diy c02 system. I would not want to harm my fish


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## Wasserpest (Jun 12, 2003)

Perhaps someone else can add their opinions too... but I think it is extremely easy to overdose a 3 gallon tank with DIY CO2 and kill all inhabitants. Depends a little on the efficiency, how much CO2 is dissolved in water and how much surface agitation and gas exchange takes place.

It is very difficult to keep water parameters fairly constant in a miniature tank like this. Adding CO2 is possible, but will make it even more complex and prone to sudden changes.

I am admiring beautiful nanos. The smaller a tank, the more difficult it is to maintain stability... nuff said.


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## Guttboy (Jul 19, 2003)

Wasserpest....i am unfamiliar with the type of tree you are talking about....are you just using any old bark for this? Could you possibly use cork from a wine bottle...providing of course you did not get TOOOO much wine in the tank....LOL.

Mike


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## Wasserpest (Jun 12, 2003)

Mike,
You can't use bark or cork. I was just using little pieces of branches that fit into an airline to get very fine bubbles, almost like dust. BUT this was about a millenium ago, and I suppose it's much easier to go to the next pet shop and buy the finest airstone you can find.
:mrgreen:


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## GulfCoastAquarian (Jul 30, 2002)

Wasserpest said:


> Perhaps someone else can add their opinions too... but I think it is extremely easy to overdose a 3 gallon tank with DIY CO2 and kill all inhabitants.


I agree. In a tank this small, an efficient reactor could drop pH levels very quickly, even in well-buffered water. I've always just injected CO2 into the inlet of my tiny Whisper Power Filter. It efficiently dissolved the CO2 gas, and if CO2 levels threaten to get too high, the waterfall allows for enough gaseous exchange with the atmosphere to released excess CO2.


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