# What is cheapest way to get DIY C02? citric acid, yeast and sugar?



## Darkblade48 (Jan 4, 2008)

For DIY CO2, either of those methods would be fairly cheap, as it is likely you have the materials around the house. You might save a few pennies using baking soda and citric acid, since yeast is probably a bit more expensive.

If you are looking at the long term, however, then pressurized CO2 is the way to go.


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## mik778866 (Aug 22, 2014)

Hi. If citric acid works out cheaper in your area, it would definitely be a better method, as this allows u to control output much better by making adjustments to the needle valve. 


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## sevendust111 (Jul 15, 2014)

A Red Star yeast glass jar costs me like 6 buck and lasts for 4-5months.


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## Nordic (Nov 11, 2003)

Citric acid mixture is more risky, you get it slightly wrong, your fish are as good as dead.


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## keymastr (May 25, 2015)

A 2 pound block of Redstar yeast is $5 at Costco. Probably a years supply or more for me. Sugar is the more expensive item but if you are very consistent about how you make your mix it is very stable and predictable.The sugar runs me about $5 a week for my 20 gallon and I get 30 - 40 PPM steady.


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## jrill (Nov 20, 2013)

Nordic said:


> Citric acid mixture is more risky, you get it slightly wrong, your fish are as good as dead.


What? That makes no sense.

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## MCSLABS (Apr 19, 2016)

This is what I'm running in my tank now.


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## Nordic (Nov 11, 2003)

remember you first get carbonic acid which then breaks down to give you the CO2.
Too much too quick and you get a pH crash. I'm sure I've read about people killing their whole tanks with it.
I guess with a small enough tank you could do the same with yeast.


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## jrill (Nov 20, 2013)

Nordic said:


> remember you first get carbonic acid which then breaks down to give you the CO2.
> Too much too quick and you get a pH crash. I'm sure I've read about people killing their whole tanks with it.
> I guess with a small enough tank you could do the same with yeast.


I don't know about killing off tanks. Before I started using it I did a lot of research and never came across that. Your not getting close to introducing any liquid to the tank, just the co2 gas at lower pressure than with a co2 cannisters. I found it easier to regulate than yeast but not as easy as a can.

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## SpaceLord (Feb 29, 2016)

MCSLABS said:


> This is what I'm running in my tank now.


Thanks for the awesome diagram. Do you manually open and close the valves or are they connected to some kind of timer or computerized system? 

Thanks.

Bump:


Nordic said:


> Citric acid mixture is more risky, you get it slightly wrong, your fish are as good as dead.


Dead from C02 overdose or acid in the tank,etc..? 

Please explain?


Sorry I am new to C02 thing. 

Thanks.

Bump:


mik778866 said:


> Hi. If citric acid works out cheaper in your area, it would definitely be a better method, as this allows u to control output much better by making adjustments to the needle valve.
> 
> 
> Sent from my ALE-L02 using Tapatalk


You can't adjust a needle valve with the yeast method? 

Is it true that the yeast method produces alcohol which could possible be released into the aquarium whereas the citric acid does not? ? 

Is this why you normally have the yeast output into a middle bottle with water to absorb alcohol before being placed in the aquarium? 


Thanks.


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## SpaceLord (Feb 29, 2016)

Darkblade48 said:


> For DIY CO2, either of those methods would be fairly cheap, as it is likely you have the materials around the house. You might save a few pennies using baking soda and citric acid, since yeast is probably a bit more expensive.
> 
> If you are looking at the long term, however, then pressurized CO2 is the way to go.



Have you ever done this DIY method in your setup? My understanding is that the Sugar is the most expensive ingredient not the yeast. 

Another member said that he spend like $5 a week on sugar but $5 a year on yeast. 

Please let me know if I got it wrong?

Thanks.


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## MCSLABS (Apr 19, 2016)

Right now I simply turn on/off the valves manually. Number 3 valve could be replaced with another check valve but the cracking pressure would have to less than the ones on the reaction vessels.


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## Watercrayfish (Apr 21, 2016)

I have two adjacent plant only tanks 10 gallon and 5 gallon( 5 gallon have dwarf hair grass carpet, java moss wall and one anubias). 12 hours I dose the 10 galllon and next 12 hrs the 5 gallon. The. lights are few inches above the water so proper rest period is there. So far no issues and I think its the most efficient way to utilize the CO2


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## Hoppy (Dec 24, 2005)

Cheapest doesn't mean best. You can set up a yeast DIY CO2 system very cheaply, so it wins the contest for start-up cost. But, after a week or so you have to spend money again on sugar, and that gets expensive after awhile, so pressurized CO2 wins the contest for operating cost. It looks to me like the citric acid method is more expensive to set-up, and costs perhaps a bit more in running cost than the yeast method.

The big downside for the yeast method is that it is very hard to get the same amount of CO2 in the water every photoperiod, and that is an open door for BBA to get started. So, if you are interested in effectiveness, even for low light tanks, the yeast method is the loser in the competition. The citric acid method is at least easier to adjust for getting the same CO2 amount every photoperiod, so it is the winner between yeast and citric acid for effectiveness. But, pressurized CO2 still wins overall because it is very easy to adjust for the same amount of CO2 every photoperiod.

That leaves the yeast method as best only in original set-up cost.


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## GrampsGrunge (Jun 18, 2012)

@ Nordic, I don't know how you get CO2 from 'Carbonic Acid breakdown', that is wrong and backwards. Carbonic Acid is formed in water with the presence of dissolved CO2. It's what changes the pH and the color of the drop checker. Running a gaseous CO2 system in an aquarium, you should have at least a carbonate hardness (dH) of about 3~6, so you have some buffering of the pH swings.


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## Hoppy (Dec 24, 2005)

GrampsGrunge said:


> @ Nordic, I don't know how you get CO2 from 'Carbonic Acid breakdown', that is wrong and backwards. Carbonic Acid is formed in water with the presence of dissolved CO2. It's what changes the pH and the color of the drop checker. Running a gaseous CO2 system in an aquarium, you should have at least a carbonate hardness (dH) of about 3~6, so you have some buffering of the pH swings.


I agree with all but the last sentence. KH does nothing to buffer the pH against CO2 injections. The combination of KH and CO2 does buffer the pH against changes caused by other weak acids, like tannic acid. CO2 and KH together adjust the pH at which the water is buffered - more KH equals higher pH and more CO2 equals lower pH. The resulting pH will be stable even if small amounts of a weak acid, other than carbonic acid, are added to the water. But, add more CO2 and the pH will drop the same amount, no matter how much KH you have. For as long as I have been reading about using CO2 in an aquarium I have never seen the buffering effect correctly explained. Most people claim that KH is a buffer, which it isn't.


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## GrampsGrunge (Jun 18, 2012)

Hoppy said:


> I agree with all but the last sentence. KH does nothing to buffer the pH against CO2 injections. The combination of KH and CO2 does buffer the pH against changes caused by other weak acids, like tannic acid. CO2 and KH together adjust the pH at which the water is buffered - more KH equals higher pH and more CO2 equals lower pH. The resulting pH will be stable even if small amounts of a weak acid, other than carbonic acid, are added to the water. But, add more CO2 and the pH will drop the same amount, no matter how much KH you have. For as long as I have been reading about using CO2 in an aquarium I have never seen the buffering effect correctly explained. Most people claim that KH is a buffer, which it isn't.


 :surprise: OK good to not have presumptions about this.


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