Co2 boosting

David Music

Active Member
So a friend of mine that used to grow back in the day told me he used to run a airline for above his propane hot water heater to collect co2 from it? Anyone ever hear of this?
 

yankeetransplant

Well-Known Member
Sure, IF DONE PROPERLY....the byproduct of burning propane is Carbon Dioxide and some water vapor....Rigging something up can cause carbon monoxide if there is not enuf oxygen available to COMPLETELY burn the propane...but remember too, your hot water heater is not constantly running...just the pilot till the temp falls below the desired setting...
They make CO2 propane generators that work great and throw off VERY little heat....
 

ttystikk

Well-Known Member
The more carbon in the source material the less is needed to achieve a given ppm level of CO2.

Someone recently mentioned the use of methyl alcohol. As a liquid, it's potentially easier to work with.
 

ttystikk

Well-Known Member
Another important point to consider is that the baseline saturation of the atmosphere is now 410ppm of CO2, thanks to decades of fossil fuel usage.
 

yankeetransplant

Well-Known Member
CO2 is typically only needed in completey sealed rooms and large set ups...a typical closet garden with GOOD ventilation, really doesnt need it...I have a 5ft by 4ft closet crop PACKED wall to wall...I have a 700+ cfm exhaust fan....doesnt need CO2....If your borderline with good exhaust, try a fizz pot...I have used a 5gal bucket, 3 inches of white marble rock in the bottom (calcium carbonate)..fill bucket 2/3 with water....Put 2 holes in the top (about 1.5 inches each)....rubber stopper in each...one of them has a hole thru it for a 1/4 tubing (tight fit) the other will be used to dump a half cup of muratic acid into (quickly replug it)...the reaction boils the water with CO2, which oozes out the tubing, wired to the back of one of your circulation fans...It produces a BUNCH of CO2...
 

fearnoevil

Well-Known Member
Well I'm finally coming around to trying CO2 in order to push my girls to the limit, everything I've read says it's probably the one thing I haven't tried that I should (me, stubborn ;?).

But living in the sticks, I'm running into the same problems I've heard from some other growers, that is it's getting harder to find places to get their tanks refilled. And I'm talking about 10 lb tanks or larger, not the little ones at Walmart for paintball guns.

One place that's about 40 minute drive from me is charging $26 bucks plus tax for a 10 lb refill, or about $2.75 per lb (and that's if you can trust them to fill them full, have read some complain that they're often a bit on the shy side). That drops considerably if you go with a 20 lb tank for $35, but the cost for an empty tank is not cheap.

But from what I can find for comparison, it seems that a pound of dry ice has potentially the same volume of CO2 as a pound of the compressed/liquid, give or take .5 cu. ft. If that's true, btw I can pick up dry ice at my local grocery store for $1.65 (tax incl) per lb, and considering the convenience/proximity and that I don't have to invest all that money on tanks, valves and controllers (close to a $400 savings up front) it seems a to be a cheaper alternative. So I'm considering trying that route at least for a trial run to see how much improvement I get. If I like it I can always spring for the full system on the next crop.

Cons for the dry ice route would be that you have little control over how much CO2 is being released and no way to shut it off, and buying 10 lbs every few days might cause suspicion, although I could spread that around between 3-4 different stores.

Controlling how fast the dry ice sublimates could be partly controlled by insulating the container, say a cooler with added sheet styrofoam - maybe 10 lbs could be made to last 48hrs in a cooler with some holes drilled for tubes to distribute it, plus a fan for assist. And while far less than ideal, I'd think that there would be a measurable benefit even from intermittent CO2 supplementation, say 48 hrs. twice a week.

I'm sure I'm not the first to try this, nothing new under the Sun as they say, so anyone have any xp doing this, or educated opinions?
 

cindysid

Well-Known Member
Try to find a larger tank. I found a 75 pounder on Craigslist for $60.00. It costs me about $50.00 to refill at Airgas. It's one of their tanks, so they just exchange with me every time. The downside is the weight. It takes a dolly to move it around and going up and down stairs is no fun, but I only have to refill about every two months and I'm running it in a 10 x 10 room.
 

fearnoevil

Well-Known Member
Try to find a larger tank. I found a 75 pounder on Craigslist for $60.00. It costs me about $50.00 to refill at Airgas. It's one of their tanks, so they just exchange with me every time. The downside is the weight. It takes a dolly to move it around and going up and down stairs is no fun, but I only have to refill about every two months and I'm running it in a 10 x 10 room.
That sounds about perfect, mines 11"x 12" but with on a little over 7" ceiling. I have been looking on Craigs, but no luck on anything cheap, just gonna keep my eyes and ears peeled for the next few month. Otherwise there's 50 pounders on Amazon for $349 which is why I liked the 10 ld for $89. I shall have to do some calcaputen here and figure out the best way to gol
 

0321Marine

Well-Known Member
You can spend a few dollars and get the same results, if not better, by using simple cheap methods.

I have my 3'x3' tent area - testing at around 1200-1400ppm using only an ethanol bottle that I made and a spore/straw bag. And at those Co2 levels, with a mostly sealed room.. the plant has shown amazing growth. She loves it in there.

Start small, with manageable things that you understand. If you research the science of Co2, how plants take it in and benefit from it, and then how Co2 can be made.. you'll be amazed at your end product if you apply that knowledge.
 

kratos015

Well-Known Member
Well I'm finally coming around to trying CO2 in order to push my girls to the limit, everything I've read says it's probably the one thing I haven't tried that I should (me, stubborn ;?).

But living in the sticks, I'm running into the same problems I've heard from some other growers, that is it's getting harder to find places to get their tanks refilled. And I'm talking about 10 lb tanks or larger, not the little ones at Walmart for paintball guns.

One place that's about 40 minute drive from me is charging $26 bucks plus tax for a 10 lb refill, or about $2.75 per lb (and that's if you can trust them to fill them full, have read some complain that they're often a bit on the shy side). That drops considerably if you go with a 20 lb tank for $35, but the cost for an empty tank is not cheap.

But from what I can find for comparison, it seems that a pound of dry ice has potentially the same volume of CO2 as a pound of the compressed/liquid, give or take .5 cu. ft. If that's true, btw I can pick up dry ice at my local grocery store for $1.65 (tax incl) per lb, and considering the convenience/proximity and that I don't have to invest all that money on tanks, valves and controllers (close to a $400 savings up front) it seems a to be a cheaper alternative. So I'm considering trying that route at least for a trial run to see how much improvement I get. If I like it I can always spring for the full system on the next crop.

Cons for the dry ice route would be that you have little control over how much CO2 is being released and no way to shut it off, and buying 10 lbs every few days might cause suspicion, although I could spread that around between 3-4 different stores.

Controlling how fast the dry ice sublimates could be partly controlled by insulating the container, say a cooler with added sheet styrofoam - maybe 10 lbs could be made to last 48hrs in a cooler with some holes drilled for tubes to distribute it, plus a fan for assist. And while far less than ideal, I'd think that there would be a measurable benefit even from intermittent CO2 supplementation, say 48 hrs. twice a week.

I'm sure I'm not the first to try this, nothing new under the Sun as they say, so anyone have any xp doing this, or educated opinions?
I prefer propane generators personally. A lot easier to find a place to refill a propane tank than it is a CO2 tank. And filling a 20g propane tank isn't nearly as sketchy as filling a 20lb CO2 container. The generator+controller will run you around $450-$500 though.
 

fearnoevil

Well-Known Member
I prefer propane generators personally. A lot easier to find a place to refill a propane tank than it is a CO2 tank. And filling a 20g propane tank isn't nearly as sketchy as filling a 20lb CO2 container. The generator+controller will run you around $450-$500 though.
Well that's a no-go for me, I already have enough heat issues to deal with without adding more, plus I just don't trust something like that inside my basement because if something goes awry and the flame isn't clean then there's a chance of CO buildup, and I don't want to wake up dead one morning, lol.

I have been experimenting with dry ice starting 10 days ago, putting an 8-10 lb block in my grow room every 2-3 days and I absolutely believe its making a difference. My plants look greener and healthier than they were before and since I'm now in the 4th week of flower, they're really starting to put out some nice flowers. Plus found dry ice even cheaper for $1.58 a lb, tax incl. so it's about $13-$16 per application so I think I'll average about $36 per week. I was only planning on running this til week 6 or 7 due to a lot of feedback about some downside to high CO2 supplementation in the last few weeks.

BUT I forgot I've got more plants lined up to go into the flower room in about 2 weeks, so I may have to run it all the way through to chop on the first batch. I guess it'll be an interesting experiment to see if too much CO2 actually does reduce flavor/scent/THC production or make airy buds. I do have my last harvest to compare to since the first batch is all DJ Short Shortbread from seeds I produced last year, so I do have a baseline to compare to (somewhat, not having used CO2 before). Vamos a ver, eh ;?D
 

fearnoevil

Well-Known Member
BTW, I've heard lots of comments about how CO2 is heavier than air and so you have to worry about it "pooling" on the floor, and I think there has to be some modification to that idea. While it is true that it is heavier than the air around us, and that you can actually prove that in some type of container, like a mason jar where CO2 can be used to displace oxygen/air. ButI believe that only applies to small environments with minimal exposed surfaces. For instance I don't think you'd get the same effect using a pie pan, or at least only temporarily.

Logically we know that CO2 is a constituent part of the air we breath, and that it's pretty evenly spread out and tends to stay that way, kind of like a dissolved solid, like salt, will stay in suspension in a glass of water. While there's certainly a lot of movement in the air around us, whether by wind or solar powered updrafts etc. that someone might claim accounts for this, the fact is this CO2, to my knowledge, never exhibits any tendency to pool or separate from the surrounding air itself.

If it could, you'd expect to be able to measure this stratification in say a canyon or isolated valley during extended windless periods without thermal intervention, say in the dead of winter. But I haven't seen or heard of such phenomena, and I think that the same would apply in your grow area. As long as you have a fan on during the application of the CO2, I would think that once it was mixed with the air that even turning off your fans would not allow it to settle or pool.

Maybe this is an obvious point, but from the comments I've read it does seem that some people may have a misunderstanding about the nature of CO2. Now I could be wrong, and without much XP to go on I'm just basing my opinion on my understanding of science (which is also limited ;?). Anyone have any opinions or XP to the contrary?
 

0321Marine

Well-Known Member
BTW, I've heard lots of comments about how CO2 is heavier than air and so you have to worry about it "pooling" on the floor, and I think there has to be some modification to that idea. While it is true that it is heavier than the air around us, and that you can actually prove that in some type of container, like a mason jar where CO2 can be used to displace oxygen/air. ButI believe that only applies to small environments with minimal exposed surfaces. For instance I don't think you'd get the same effect using a pie pan, or at least only temporarily.

Logically we know that CO2 is a constituent part of the air we breath, and that it's pretty evenly spread out and tends to stay that way, kind of like a dissolved solid, like salt, will stay in suspension in a glass of water. While there's certainly a lot of movement in the air around us, whether by wind or solar powered updrafts etc. that someone might claim accounts for this, the fact is this CO2, to my knowledge, never exhibits any tendency to pool or separate from the surrounding air itself.

If it could, you'd expect to be able to measure this stratification in say a canyon or isolated valley during extended windless periods without thermal intervention, say in the dead of winter. But I haven't seen or heard of such phenomena, and I think that the same would apply in your grow area. As long as you have a fan on during the application of the CO2, I would think that once it was mixed with the air that even turning off your fans would not allow it to settle or pool.

Maybe this is an obvious point, but from the comments I've read it does seem that some people may have a misunderstanding about the nature of CO2. Now I could be wrong, and without much XP to go on I'm just basing my opinion on my understanding of science (which is also limited ;?). Anyone have any opinions or XP to the contrary?
The only concern for growers when it comes to Co2, is the chance of creating a "vapor barrier". This is where the Co2 does not get taken in by the plant, due to no air circulation.

It really is not a concern at all, because no one leaves the air completely stale in the room, while adding Co2... literally no one does that, and if they do.. they learn a lesson.
 

Gritzman

Member
CO2 is typically only needed in completey sealed rooms and large set ups...a typical closet garden with GOOD ventilation, really doesnt need it...I have a 5ft by 4ft closet crop PACKED wall to wall...I have a 700+ cfm exhaust fan....doesnt need CO2....If your borderline with good exhaust, try a fizz pot...I have used a 5gal bucket, 3 inches of white marble rock in the bottom (calcium carbonate)..fill bucket 2/3 with water....Put 2 holes in the top (about 1.5 inches each)....rubber stopper in each...one of them has a hole thru it for a 1/4 tubing (tight fit) the other will be used to dump a half cup of muratic acid into (quickly replug it)...the reaction boils the water with CO2, which oozes out the tubing, wired to the back of one of your circulation fans...It produces a BUNCH of CO2...
How long will it produce Co2?
 
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