CO2 via Yeast The Right Way, With Calculations..

born2killspam

Well-Known Member
Under anaerobic conditions, yeast (Saccharomyces cerevisiae) harvest oxygen from glucose yielding ethyl alcohol, and CO2.. They actually evolve small quantities other other things such as ethylene, which is a plant hormone associated with ripening..
Alot of ppl already know you can produce CO2 with yeast, and sugar, but alot of the instructions and recipes I've seen are unreliable.. I'll get to a good lazy man recipe, but I gotta start by saying that its a shame if thats what you choose.. The best thing to do is seek out a forum on brewing, wine-making, or distilling and master a symbiotic hobby to this one..

Anyways, the numbers.. There are a number of aspects to look at regarding numbers.. Yeast specific numbers, sugar specific numbers, alcohol specific numbers, even exhaust rate, gas law and molar calculations..
Baker's yeast can tolerate up to 14% abv before succumbing to death by their own waste.. Other specialty yeasts can survive higher levels up to 18-19%.. All yeast function best when they aren't pushed to their limits, but each have their pros/cons for various fermentations..
Yeast can only handle sugar concentrations ~30-35% by mass.. Beyond this their cell walls get trashed..
Yeast can process sugar in two different modes.. Fermentation producing alchohol is the anaerobic mode..
C6H12O6 -> 2CO2 + 2C2H5OH + heat
For fastest/cleanest fermentation, sugar should be inverted, but I don't want to get into that now.. Its on google..
There is also an aerobic mode that yields no alcohol, but 3x as much CO2 and baby yeast..
C6H12O6 + 6O2 -> 6CO2 + 6H2O + more heat
Notice the fact that baby yeast aren't in that eq'n.. That brings up a good point.. YEAST DO NOT EAT SUGAR!!! Its an energy source for other chemical reactions more like breathing.. And yeast need to eat too, in reproductive mode they need alot of actual food.. Thats why I'll be stressing food sources when I get to recipes..
So those eq'ns bring us to some mole math.. A mole is like a dozen, except its waay bigger, and isn't an arbitrary number 1mole (602000000000000000000000 of anything) of protons weighs 1g.. This means that the mass of a mole of atoms weighs its atomic number in grams..
CO2 has a molar mass of 44g, glucose [C6H12O6] has a molar mass of 180g.. From the eq'ns we see that the ratios of CO2 to glucose are 2:1 and 6:1 respectively, so by mass it works out that the CO2 yield under anaerobic conditions is about 50% initial sugar mass, and about 150% initial sugar mass in reproductive mode..
Another thing about moles is that we can use them to estimate CO2 ppm..
A mole of a gas like CO2 will occupy 22.4L (~0.8cuft) at standard temperature/pressure.. 1mole of CO2 in 22.4L at STP would be 1000000ppm.. Our ideal target is about 1500ppm, which 667x diluted.. So 44g of CO2 produces about 15000L (530cuft) of ideal plant air, but stationary the CO2 will pool at the bottom.. Knowing how many cfm your grow room cycles, and being able to estimate the CO2 production rate its possible to scale towards a roughly correct stable concentration.. I can help you with this math if you ask..
Steady CO2 output from a single fermentation batch is impossible (not as impossible under reproductive conditions since very little alcohol is evolved).. If you want to keep controlled levels you'd need to get really good at making yeast happy, AND use multiple batches stagger started and always cycling.. But really if you care that much about the CO2 stability you should spend money on a bottle/burner and a meter..

I know I said its a shame to not brew up something tasty, but to address the mechanics thats what I'm going to post.. This can be scaled to need, but scaling a fermentation extremely may make it ferment a bit differently..
I'm going to work with Litres since there is only one kind.. Sorry Americans..
Dependable Sugar Wash 10L
For this measurements don't need to be precise, I'm leaving wiggle room..
For fastest results use dechlorinated water.. If your water is chlorinated with chlorine then that is as simple as letting it sit in the sun for a while.. If its chlorinated with chloramine, then its more persistent.. Vitamin C helps break it up I believe, I forget what else is involved.. I don't have to deal with that.. You can call your water supplier to find out if you do.. Ppl with aquariums need to deal with it so answers are easy to get..

-If yeast is in fridge/freezer, get some out now to warm.. The more the better, but its not critical for this wash.. I might use 3 little packs, or 1-2oz of bulk yeast for this if I'm not making a yeast starter batch..
-Heat 2-3L of water hot enough to dissolve sugar easily..
-Dissolve ~1.75kg (4lbs) sugar in that water..
-Squirt in a few tsp of lemon juice.. (Acidic conditions [high 4's] help to keep bacteria at bay, and also help invert sugar for yeast)
-Mix in a food source for them.. A can of tomato paste is great, potato water, cereal, fruit, concentrated juice and many other things are also good.. A crushed multivitamin is pure gold.. As long as you give them something they're happy..
-Optionally put in a half tsp of high N fertilizer.. Ideally DAP (diammonium phosphate).. this energizes yeast and helps speed stuff up.. Brew stores sell some sweet yeast energizer/nutrient blends
-Top it up to 10L with cold water
Make sure its within 75-85°F Yeast can survive warmer, but warmer water holds less O2.. Aerate the hell out of it! I'm not kidding we want O2 in there initially to the yeast can build their colony.. When they're done the population will be about 10-20million cells/mL! This is why we need food.. Yeast contain tons of things that aren't in sugar..
-Add yeast and give it a little stir.. Cover it up and keep it at whatever temperature your grow is.. In 2-12 hours it should be sounding like a glass of ice that just had soda poured on it, and should ferment to about 10.5%abv in 4-5 days..

Over its active period that batch will evolve about 2lbs (~20moles) of CO2, which would mix up to 300000L (~11000cuft) of ideal 1500ppm plant air..
From here its about considering your grow-room volume, exhaust rate, and exhaust position.. Exhaust on cieling is FAR superior to a low exhaust for CO2 containment..
It should be pretty evident though that this won't add up to much in a 2000cuft room with 560cfm exhaust, but for a contained stealth grow it could help alot.. Personally I'm under the anecdotal belief that the ethylene evolved helps my buds ripen a bit quicker..

Theres so much more that could be said.. I've been brewing and distilling for many years, and I have alot of math/science under my belt, so I have alot of experience an recipes to share.. I mainly make rums and sour mashes personally because I hate fermenting something, and not throwing it in my still a few times.. If I get a couple ppl to build themselves a still, I'll be happy with the results of this thread..
 

carcass91

Well-Known Member
Under anaerobic conditions, yeast (Saccharomyces cerevisiae) harvest oxygen from glucose yielding ethyl alcohol, and CO2.. They actually evolve small quantities other other things such as ethylene, which is a plant hormone associated with ripening..
Alot of ppl already know you can produce CO2 with yeast, and sugar, but alot of the instructions and recipes I've seen are unreliable.. I'll get to a good lazy man recipe, but I gotta start by saying that its a shame if thats what you choose.. The best thing to do is seek out a forum on brewing, wine-making, or distilling and master a symbiotic hobby to this one..

Anyways, the numbers.. There are a number of aspects to look at regarding numbers.. Yeast specific numbers, sugar specific numbers, alcohol specific numbers, even exhaust rate, gas law and molar calculations..
Baker's yeast can tolerate up to 14% abv before succumbing to death by their own waste.. Other specialty yeasts can survive higher levels up to 18-19%.. All yeast function best when they aren't pushed to their limits, but each have their pros/cons for various fermentations..
Yeast can only handle sugar concentrations ~30-35% by mass.. Beyond this their cell walls get trashed..
Yeast can process sugar in two different modes.. Fermentation producing alchohol is the anaerobic mode..
C6H12O6 -> 2CO2 + 2C2H5OH + heat
For fastest/cleanest fermentation, sugar should be inverted, but I don't want to get into that now.. Its on google..
There is also an aerobic mode that yields no alcohol, but 3x as much CO2 and baby yeast..
C6H12O6 + 6O2 -> 6CO2 + 6H2O + more heat
Notice the fact that baby yeast aren't in that eq'n.. That brings up a good point.. YEAST DO NOT EAT SUGAR!!! Its an energy source for other chemical reactions more like breathing.. And yeast need to eat too, in reproductive mode they need alot of actual food.. Thats why I'll be stressing food sources when I get to recipes..
So those eq'ns bring us to some mole math.. A mole is like a dozen, except its waay bigger, and isn't an arbitrary number 1mole (602000000000000000000000 of anything) of protons weighs 1g.. This means that the mass of a mole of atoms weighs its atomic number in grams..
CO2 has a molar mass of 44g, glucose [C6H12O6] has a molar mass of 180g.. From the eq'ns we see that the ratios of CO2 to glucose are 2:1 and 6:1 respectively, so by mass it works out that the CO2 yield under anaerobic conditions is about 50% initial sugar mass, and about 150% initial sugar mass in reproductive mode..
Another thing about moles is that we can use them to estimate CO2 ppm..
A mole of a gas like CO2 will occupy 22.4L (~0.8cuft) at standard temperature/pressure.. 1mole of CO2 in 22.4L at STP would be 1000000ppm.. Our ideal target is about 1500ppm, which 667x diluted.. So 44g of CO2 produces about 15000L (530cuft) of ideal plant air, but stationary the CO2 will pool at the bottom.. Knowing how many cfm your grow room cycles, and being able to estimate the CO2 production rate its possible to scale towards a roughly correct stable concentration.. I can help you with this math if you ask..
Steady CO2 output from a single fermentation batch is impossible (not as impossible under reproductive conditions since very little alcohol is evolved).. If you want to keep controlled levels you'd need to get really good at making yeast happy, AND use multiple batches stagger started and always cycling.. But really if you care that much about the CO2 stability you should spend money on a bottle/burner and a meter..

I know I said its a shame to not brew up something tasty, but to address the mechanics thats what I'm going to post.. This can be scaled to need, but scaling a fermentation extremely may make it ferment a bit differently..
I'm going to work with Litres since there is only one kind.. Sorry Americans..
Dependable Sugar Wash 10L
For this measurements don't need to be precise, I'm leaving wiggle room..
For fastest results use dechlorinated water.. If your water is chlorinated with chlorine then that is as simple as letting it sit in the sun for a while.. If its chlorinated with chloramine, then its more persistent.. Vitamin C helps break it up I believe, I forget what else is involved.. I don't have to deal with that.. You can call your water supplier to find out if you do.. Ppl with aquariums need to deal with it so answers are easy to get..

-If yeast is in fridge/freezer, get some out now to warm.. The more the better, but its not critical for this wash.. I might use 3 little packs, or 1-2oz of bulk yeast for this if I'm not making a yeast starter batch..
-Heat 2-3L of water hot enough to dissolve sugar easily..
-Dissolve ~1.75kg (4lbs) sugar in that water..
-Squirt in a few tsp of lemon juice.. (Acidic conditions [high 4's] help to keep bacteria at bay, and also help invert sugar for yeast)
-Mix in a food source for them.. A can of tomato paste is great, potato water, cereal, fruit, concentrated juice and many other things are also good.. A crushed multivitamin is pure gold.. As long as you give them something they're happy..
-Optionally put in a half tsp of high N fertilizer.. Ideally DAP (diammonium phosphate).. this energizes yeast and helps speed stuff up.. Brew stores sell some sweet yeast energizer/nutrient blends
-Top it up to 10L with cold water
Make sure its within 75-85°F Yeast can survive warmer, but warmer water holds less O2.. Aerate the hell out of it! I'm not kidding we want O2 in there initially to the yeast can build their colony.. When they're done the population will be about 10-20million cells/mL! This is why we need food.. Yeast contain tons of things that aren't in sugar..
-Add yeast and give it a little stir.. Cover it up and keep it at whatever temperature your grow is.. In 2-12 hours it should be sounding like a glass of ice that just had soda poured on it, and should ferment to about 10.5%abv in 4-5 days..

Over its active period that batch will evolve about 2lbs (~20moles) of CO2, which would mix up to 300000L (~11000cuft) of ideal 1500ppm plant air..
From here its about considering your grow-room volume, exhaust rate, and exhaust position.. Exhaust on cieling is FAR superior to a low exhaust for CO2 containment..
It should be pretty evident though that this won't add up to much in a 2000cuft room with 560cfm exhaust, but for a contained stealth grow it could help alot.. Personally I'm under the anecdotal belief that the ethylene evolved helps my buds ripen a bit quicker..

Theres so much more that could be said.. I've been brewing and distilling for many years, and I have alot of math/science under my belt, so I have alot of experience an recipes to share.. I mainly make rums and sour mashes personally because I hate fermenting something, and not throwing it in my still a few times.. If I get a couple ppl to build themselves a still, I'll be happy with the results of this thread..

U know ur Chemistry really well... Reminds me of my 10th grade syllabus... haha, i scored good in chemistry, i still remember the chemical equation of fermentation of sugar in presence of Zymase and Invertase to give alcohol :p:p

A very very informative Thread... a +rep for u man.
 

born2killspam

Well-Known Member
Thats worth mentioning that the equations I posted are oversimplified, and thermodynamically unfovorable without enzymes, but for the purposes of this they work..
One interesting thing along those lines though is the way yeast forms clusters that act almost like a surface catalyst to maximize those enzymatic processes..
 

carcass91

Well-Known Member
Thats worth mentioning that the equations I posted are oversimplified, and thermodynamically unfovorable without enzymes, but for the purposes of this they work..
One interesting thing along those lines though is the way yeast forms clusters that act almost like a surface catalyst to maximize those enzymatic processes..
Yes, the yeast is a bio-enzyme and act like catalysts
 

born2killspam

Well-Known Member
I'm a professional science student.. Seriously.. I still have the same job I did in university when it was a student position.. :)
 

asphyxiated2

Active Member
I'm a professional science student.. Seriously.. I still have the same job I did in university when it was a student position.. :)
We can only envy You))

Couldn't read all of it just because I'm not a native american/british, so can you give a quick plan of things you wrote?

Because I use this combination: 2l bottle, 3 eating spoons of sugar, 1/3 of yeast and fill the bottle approx. half-way. In a forum I read that if you shake a couple of times a day the mass, it can last for a week. Is this right?
 

born2killspam

Well-Known Member
Whats an eating spoon? That doesn't sound like alot.. Baker's yeast can handle just over a pound of sugar in a 2L bottle..
1lb(0.454kg)/2L will require about 1.7L of water to top up to 2L total.. It will ferment to about 13.5%abv, and yield about 220g of CO2 which will make up about 2700cuft of 1500ppm air..
BUT 13.5% is a little bit close to the limit if you want steady/quick completion.. 3/4lb on the otherhand will finish at 10%abv without slowing down at the end, and it will obviously produce 3/4 the output of 1lb (but quicker!)..
How long it will take is hard to say.. If you really know how to make yeast happy it might take 2.5 days to ferment to 10%, and 4 days to 13%.. Until you get the hang of it, you might be looking at 3x that long..
The more yeast the better, but 1 pk of that instant stuff should be more than enough for a 2L.. I'm not clear on how much you're adding.. 1/3 of what??
And don't forget to give them some healthy food in there, otherwise it may stall at partial completion..
 

Mr. Limpet

Well-Known Member
since i cant handle all this science and math stuff can you siplify it for me. i have a 2x3x5 and would like to use multiple 20oz bottles i could fit up to 6 maybe. how much water sugar yeast should be in a 20oz bottle?
and is it worth doing in my space or not?
 

carcass91

Well-Known Member
Okay, so i just got Yeast, Sugar, water and a 2L bottle... Tell me exactly how much Sugar and How much yeast?

What kind of food does the yeast like?
 

eza82

Well-Known Member
.. Personally I'm under the anecdotal belief that the ethylene evolved helps my buds ripen a bit quicker...
This is something Ive looked at with great depth and I think my thread on Hormones would intrest you...... try the RESEARCH ONLY thread in sig... find the ethylene section.
Would Luv your imput...... Discussion thread is Hormone vs Co2....come play..........:bigjoint::bigjoint::blsmoke:
+rep for stealth grow Co2 the poor mans way !;-)
 

born2killspam

Well-Known Member
since i cant handle all this science and math stuff can you siplify it for me. i have a 2x3x5 and would like to use multiple 20oz bottles i could fit up to 6 maybe. how much water sugar yeast should be in a 20oz bottle?
and is it worth doing in my space or not?
Your space seems as good a candidate as any, but what is your circulation/exhaust like? 120oz total solution would produce about 3750cuft of 1500ppm air, or about 125 total air exchanges over the fermenting period..
Anyways, if you were to use 100g of sugar topped up to 600mL(20oz) you'd get roughly the same numbers as my 10L batch, just scaled down 16-17x.. I guess I should mention that you should leave a few oz headspace to avoid bubble-overs.. The recipe I posted though allows for alot of wiggle room on the numbers before things go wrong..
As for how much yeast, again the more the better, but you could split a little pack over 2-3 of those atleast..

Another thing worth mentioning is a yeast starter.. When I ferment, I mix up an ultra nutritious solution weak in sugar, aerate the heck out it with a stone, and add my yeast.. I keep adding a little at a time as they use it up, and increase the volume of solution as the colony grows.. When I'm done I have a few gallons of starter solution teeming with a few hundred times as many yeast as I initially added..
Its not much different than how bakers prep yeast, but much larger scale.. When yeast are happy and in O2 they can double population in 3-4hrs..
BTW you'd get best results if you stagger started those bottles 1/day.. That would give you near consistent output over the week or so..
 

born2killspam

Well-Known Member
Okay, so i just got Yeast, Sugar, water and a 2L bottle... Tell me exactly how much Sugar and How much yeast?

What kind of food does the yeast like?
-Heat 1/2L or so to make it dissolve well..
-Add 3/4lb(~350g) sugar
-For food, molasses, tomato paste, concentrated juice, potato (or water from boiling potatos), cereal, flour tortillas.. Heck throw some compost in there if you don't plan on drinking it.. Yeast are not picky eaters, they just need to eat.. Really this choice will likely only affect the final flavor.. Most fermented drinks are centred around the food source like grapes in wine..
-Squirt in some lemon juice (couple caps worth maybe).. Creme of tartar can also be used.. You want high 4's pH ideally..
-Top up with cold water
-Make sure it isn't above 100F
-Shake like mad to aerate
-Add yeast (one of those instant packs is roughly a tsp..)

I can't imagine the hassle of batches this small though.. I usually ferment atleast 80L at a time.. And I never did my math for my own grow space either.. I was fermenting for the alcohol, and figured my grow room was the ideal place..
 

born2killspam

Well-Known Member
This is something Ive looked at with great depth and I think my thread on Hormones would intrest you...... try the RESEARCH ONLY thread in sig... find the ethylene section.
Would Luv your imput...... Discussion thread is Hormone vs Co2....come play..........:bigjoint::bigjoint::blsmoke:
+rep for stealth grow Co2 the poor mans way !;-)
Ahh my very favorite type of thread.. I'd like to check it out right now, but I fear that if I do I won't get around to a couple things I need done tonight.. Honestly I'm surprised I didn't know that thread existed..
 

eza82

Well-Known Member
Ahh my very favorite type of thread.. I'd like to check it out right now, but I fear that if I do I won't get around to a couple things I need done tonight.. Honestly I'm surprised I didn't know that thread existed..
I look forward to some input...... :bigjoint::blsmoke:
 

carcass91

Well-Known Member
-Heat 1/2L or so to make it dissolve well..
-Add 3/4lb(~350g) sugar
-For food, molasses, tomato paste, concentrated juice, potato (or water from boiling potatos), cereal, flour tortillas.. Heck throw some compost in there if you don't plan on drinking it.. Yeast are not picky eaters, they just need to eat.. Really this choice will likely only affect the final flavor.. Most fermented drinks are centred around the food source like grapes in wine..
-Squirt in some lemon juice (couple caps worth maybe).. Creme of tartar can also be used.. You want high 4's pH ideally..
-Top up with cold water
-Make sure it isn't above 100F
-Shake like mad to aerate
-Add yeast (one of those instant packs is roughly a tsp..)

I can't imagine the hassle of batches this small though.. I usually ferment atleast 80L at a time.. And I never did my math for my own grow space either.. I was fermenting for the alcohol, and figured my grow room was the ideal place..

So, i just need a TBS of Yeast for 2L water and sugar mix??

Thats kool enough. So, for how many days is the co2 generation active?
 

born2killspam

Well-Known Member
Yea.. You 'could' get even away with alot less, even none if you get lucky and a natural strain innoculates it..
Yeast initial quantity will affect speed obviously, and flavor because even though we go through a reproductive phase at the start, with a balanced diet its really tough to grow them as well as the pros, so after too many generations of reproduction they get a tad retarded, and start producing more fusil oils and whatnot..
A funny thing is that best results seem to occur when you have just the right proportion of new: original because early generations acclimate best to the environment they're born in, and happy yeast ferment cleanest..
Atleast this is the common observation in the distilling scene..

Edit: Again, times will vary.. Higher temps will speed things up until about 100F or a little more.. Dechlorinating your water as I said helps speed alot.. Yeast nutrients and DAP from a brewstore are easy improvements to any recipe.. Inverting your sugar can help too.. Most of the add-ons are a bit overkill and extra work if you don't intend to drink it though.. Not only do the add-ons improve speed, but also quality..
If you get done the basic recipe in 4 days then you're well on your way to getting good at this, but sometimes mysteries can slow things down quite a bit..

And I just realized I haven't mentioned sanitation at all, sorry.. Its best to soak everything in a bleach or peroxide solution before rinsing/using.. Bacteria are waay better at reproducing than yeast, and if you catch an early infection, they can take over pretty quick..
 

epixbud

Well-Known Member
hay born2killspam...... i wanna get CO2 into my room, totally lost me with all the calc's... he he he.... i can't really bring co2 canisters here, too noticable, would totaly apretiate your advise on how to set it up for my room...

my flower room is 8' long x 5' wide and 8' high..... i got a 440cfm inline exaust fan pull thro a carbon filter......it's got 2 x fresh air lines, 1 pushin 200cfm and the other pushin 150cfm, there is 1 osculating fan and 3 stationary ones thro out...
i can't turn the exaugst off at all as all my lights are in vented hoods via the exaughst line.......

i can't get my flower temps to stay less then 92.... so there's the hot temp and lights out temp 75....

check out my grow if ya want https://www.rollitup.org/grow-journals/107075-ak-47-x-super-silver-27.html
 

born2killspam

Well-Known Member
One of the points of vented lights is to reduce the exterior exhaust needs so you can easier manage CO2.. That setup as you have it running now isn't exactly suitable for any type of enrichment.. Ideally you should have the intake > light > exhaust for the cooled hoods isolated from the room..
 
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