Cheap Way to make CO2 for your grow

Little Tommy said:

Here is a picture of a simple fermentation setup that I have used. I keep a towel wrapped up on the outside of the glass. The yeast seem to work better in the dark.

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needhelp said:

you can use Seltzer water but i didn't want to mention it because you have people on here who swear you shouldn't give plants Seltzer water and they say the roots don't need CO2, just oxygen.... when in reality they are WRONG... I am not an expert grower but the reason i know they are wrong.. 1) i tried it and it didn't harm my plants at all 2) i looked up a study done with 2 plants Water Vs. Seltzer Water... it showed a chart and the experiment was done over a series of months...so it wasn't a bullshit study... and the plant fed Seltzer Water actually grew healthier and bigger than the plant that was fed water... (it even became smarter.... meaning... when certain leaves started to die when they conducted a dry experiment... the plant started to grow leaves at the bottom instead of the top like every plant that is fed water) because the theory is since plants roots do need oxygen... the bubbles are feeding both to the roots and people didn't know roots can benefit from CO2 because of the whole plant leaf using CO2 thing.... and what was also a plus sign... the bubbles help loosen dirt around the plants roots so they do have the room to breathe easier.... there are many that will dispute this... but like i said... i looked it up for myself because you can't depend on weed growers to know and understand all aspects of plant life.... you also need people who know plants.... just make sure its seltzer water with NO SODIUM... maker sure its all zeroes in the nutrional column on the back of the bottle.... oh yeah.... there are people on here that will say don't water your plants seltzer water...just spray it... i don't know anything about this or if it works... but i do know you can give your plant seltzer water as long as there's NO SODIUM

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Anonymous said:

Baking soda/acid is a good system, but it is ultimately fairly expensive. Furthermore, you also release acetate ions/salts, as well as other volatiles from the vinegar (which is not a pure solution of acetic acid, of course). They prolly won't kill your plants, though they might. Instead they will likely make it smell or taste bad.

What is a better way to get your carbon dioxide? Fermentation. Acquire some brewer's yeast if you can. The types of yeast you can use are in order of what is best, though all are acceptable:

Champagne
Wine
Ale
Beer
Baker's

Rig up a simple fermentation chamber with airlock. The airlock is designed to keep the atmosphere anaerobic while releasing your good CO2. Fermentation chamber should be any airtight container with top. It could be a 2 liter Coke bottle, for example. Drill a hole in its top and glue in some plastic tubing, making sure to create a good seal. An epoxy is prolly what you'll need to do it. Run that tube into a smaller, halved bottle: a water bottle works well. Place the tube at the exact bottom and glue it there such that the outlet of the tube faces the wall (not the bottom) and is not blocked (by glue, the wall, your mouse, whatever). Fill that up with water, about an inch and a half above the bottom.

The mechanism is all set up, now set up the fermentation. Fill the bottle with about a 20% solution of glucose (dextrose) by mass and place a few tsp. of yeast in that jaunt. Placing the yeast in some warm water for half an hour prior with some sugar is a good way to jump-start the process. Using those six-carboned sugars, you get optimum results, but other sugars can be used. In general, you'll likely find the 5-carbon variety (fructose: corn syrup, eg.) or the polysaccharide (sucrose: cane sugar). In these cases, its ok to add a little more sugar, no more than 25%. Champagne yeast can tolerate more. Brewers yeast, you may want to shoot for less. Cap that jaunt with the tubing/cap system you rigged up.

Here's the principal, its perty simple: The yeast use the sugar to make their energy (ATP). However, in absence of oxygen, the metabolic pathways can't be completed, and alcohol is excreted as waste. This is disadvantageous to the yeast, but hey, who cares? They also release carbon dioxide. For every equivalent of glucose or dextrose, the yeast produces two equivalents of carbon dioxide and alcohol. If other sugars are used, the process is slightly less efficient due to the early metabolics that get done to prepare it, or the inefficiency of metabolic/synthetic shunts (biochemical shite, its unimportant, but fun if you are nerdy). The carbon dioxide is good for your plants: its the objective. The alcohol is bad. It increases in concentration in the fermentation vessle and DOES NOT leave in any way. Over time, the yeast poisons itself with its own waste. Better yeasts (as per the above sheet) survive longer and make more carbon dioxide. Hence the reason for increasing the sugar, if you'd like (the difference is probably just about marginal if at all, so don't dwell on it).

So what does this mean for you? A mole of glucose is around 180 grams. Thus, a 20% mass solution will produce slightly more than TWO MOLES (2.2 to be be exact) of of gas per liter. At standard temperature and pressure, and if you are growing, that's what you want, you will get around 50 liters of pure carbon dioxide from this method, over the time period of about 2-4 weeks. Great stuff.

Problems: You can tell the yeast are dying when the bubbling through the airlock subsides. No way around it, you need to whip up another fermentation mixture. Optimally you would do this every week and a half, while the yeast are at their maximum productivity. Using cane sugar and baker's yeast this is a crazy inexpensive endeavour.

Can you kill the plants with too much CO2? Most likely not. They breathe it as air, and they really only need oxygen (the only other thing they really take from the air) to run their ETC and some other minor metabolic processes. They get this from the water, believe it or not. Also they respirate as much 02 as they take in CO2. No problem, really. Time when killing the plants from carbon dioxide have been reported is likely either in extreme cases (approaching NO oxygen in the air and thus water) or due to the poor downsides to using other carbon producing methods (acidic air, contamination of various sorts, etc.). On the other hand, your plants would optimally have about 3 times as much carbon dioxide as would be in the atmosphere. That rings in at around 6%, so not that much, and in all likelihood, its gonna be difficult to bring it up to these levels. Happy planting.

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whatsawhosit said:

excellent post but lets make it simpler!!! why all the hoses and extra jugs just to lock out oxygen?

i just took a jug punched a hole in the top and epoxied a cheap plastic check valve in there. the same kind of valve aquarium filters use that prevent the water from backing up into the air pump. two dollars at wal mart

http://www.marinedepot.com/ps_viewitem.aspx?idproduct=AZ0031&child=AZ0031&utm_source=mdcsegooglebase2&utm_medium=cse&utm_campaign=mdcsegooglebase2&utm_content=AZ0031


something like that.


now you don't have hoses and jugs, heck in my set up I need four of these babies that would leave my place looking like a mad scientist lab form back to the future or something!!

the heat yeast makes is negligible and does nothing. just the creation of co2 itself will force all the air out of the jug in a few minutes and then your valve will be sending out JUST co2 and not allowing air back in

once you have done this you have a very easy way to attach a hose to your co2 generator and run those over and through the growing area so that you get a good coverage.

my 2 cents

Click to expand...

Anonymous said:

Baking soda/acid is a good system, but it is ultimately fairly expensive. Furthermore, you also release acetate ions/salts, as well as other volatiles from the vinegar (which is not a pure solution of acetic acid, of course). They prolly won't kill your plants, though they might. Instead they will likely make it smell or taste bad.

What is a better way to get your carbon dioxide? Fermentation. Acquire some brewer's yeast if you can. The types of yeast you can use are in order of what is best, though all are acceptable:

Champagne
Wine
Ale
Beer
Baker's

Rig up a simple fermentation chamber with airlock. The airlock is designed to keep the atmosphere anaerobic while releasing your good CO2. Fermentation chamber should be any airtight container with top. It could be a 2 liter Coke bottle, for example. Drill a hole in its top and glue in some plastic tubing, making sure to create a good seal. An epoxy is prolly what you'll need to do it. Run that tube into a smaller, halved bottle: a water bottle works well. Place the tube at the exact bottom and glue it there such that the outlet of the tube faces the wall (not the bottom) and is not blocked (by glue, the wall, your mouse, whatever). Fill that up with water, about an inch and a half above the bottom.

The mechanism is all set up, now set up the fermentation. Fill the bottle with about a 20% solution of glucose (dextrose) by mass and place a few tsp. of yeast in that jaunt. Placing the yeast in some warm water for half an hour prior with some sugar is a good way to jump-start the process. Using those six-carboned sugars, you get optimum results, but other sugars can be used. In general, you'll likely find the 5-carbon variety (fructose: corn syrup, eg.) or the polysaccharide (sucrose: cane sugar). In these cases, its ok to add a little more sugar, no more than 25%. Champagne yeast can tolerate more. Brewers yeast, you may want to shoot for less. Cap that jaunt with the tubing/cap system you rigged up.

Here's the principal, its perty simple: The yeast use the sugar to make their energy (ATP). However, in absence of oxygen, the metabolic pathways can't be completed, and alcohol is excreted as waste. This is disadvantageous to the yeast, but hey, who cares? They also release carbon dioxide. For every equivalent of glucose or dextrose, the yeast produces two equivalents of carbon dioxide and alcohol. If other sugars are used, the process is slightly less efficient due to the early metabolics that get done to prepare it, or the inefficiency of metabolic/synthetic shunts (biochemical shite, its unimportant, but fun if you are nerdy). The carbon dioxide is good for your plants: its the objective. The alcohol is bad. It increases in concentration in the fermentation vessle and DOES NOT leave in any way. Over time, the yeast poisons itself with its own waste. Better yeasts (as per the above sheet) survive longer and make more carbon dioxide. Hence the reason for increasing the sugar, if you'd like (the difference is probably just about marginal if at all, so don't dwell on it).

So what does this mean for you? A mole of glucose is around 180 grams. Thus, a 20% mass solution will produce slightly more than TWO MOLES (2.2 to be be exact) of of gas per liter. At standard temperature and pressure, and if you are growing, that's what you want, you will get around 50 liters of pure carbon dioxide from this method, over the time period of about 2-4 weeks. Great stuff.

Problems: You can tell the yeast are dying when the bubbling through the airlock subsides. No way around it, you need to whip up another fermentation mixture. Optimally you would do this every week and a half, while the yeast are at their maximum productivity. Using cane sugar and baker's yeast this is a crazy inexpensive endeavour.

Can you kill the plants with too much CO2? Most likely not. They breathe it as air, and they really only need oxygen (the only other thing they really take from the air) to run their ETC and some other minor metabolic processes. They get this from the water, believe it or not. Also they respirate as much 02 as they take in CO2. No problem, really. Time when killing the plants from carbon dioxide have been reported is likely either in extreme cases (approaching NO oxygen in the air and thus water) or due to the poor downsides to using other carbon producing methods (acidic air, contamination of various sorts, etc.). On the other hand, your plants would optimally have about 3 times as much carbon dioxide as would be in the atmosphere. That rings in at around 6%, so not that much, and in all likelihood, its gonna be difficult to bring it up to these levels. Happy planting.

Click to expand...