cannabis is a c3 plant might want to check that out it might help you mr greengenes
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Sealed Rooms and night time oxygen
- Thread starter Seltzerman
- Start date
lol... well damn it man!! don't run the Co2 after lites out then... prob solved
I run sealed with a burner for Co2.
you don't run Co2 at nite, if you are your doing it wrong.
and really you don't need to exhaust anything other than the
humidity spike that goes on after lites out,
and a dehuey takes care of that.
if you want to exhaust thats an option.
but what ever way you go turn off your Co2 at nite.
the Co2 burner is no more likely to use all the o2 in the room anymore than you in it
the room has to very very very small for a burner to starve O2 in the room.
we're talking like a small walkin closet.
and you don't run a burner in the closet gro
tanks are used for smaller rooms, burners for larger because of it's economic advantage
Ive been running sealed with a C02 burner for 1-1/2yrs now with no probs in the lack of O2 dept.
plants breathe in C02 and exhale O2, Ive spent many a hour in the room and have come nowhere close to depleting the O2 in the room. to the contrary, the longer i'm in i'll raise the Co2.
which the plants love, they give me O2 and I give them Co2
DunHav`nFun
Well-known member
Well damn it man.....lol... well damn it man!! don't run the Co2 after lites out then... prob solved
I run sealed with a burner for Co2.
you don't run Co2 at nite, if you are your doing it wrong.
and really you don't need to exhaust anything other than the
humidity spike that goes on after lites out,
and a dehuey takes care of that.
if you want to exhaust thats an option.
but what ever way you go turn off your Co2 at nite.
.....Keep em straight gnomester.....The plants will uptake and use/metabolize as much CO2 as possible during lights on , and shit out excess CO2 plus water vapor left over lights out , and that`s why a lot of the bigger growers with warehouse sized setups use exhaust at night , but not many speak of the lil trade secret....but...
Dehuey`s do their job well in smaller setups in a sealed environment during lights off , and be sure to monitor RH during mid-late flower till end of cycle to prevent air born nasties from taking hold....anyways.....
Good luck....DHF.....
I am having issues in my room with O2 levels. My room is 700 sq ft with 13 ft ceilings. I have a propane 8 burner co2 generator. My oxygen levels are 18.0-18.5 in the room. I have poisoned my plants a few times already because (I think?) of oxygen depletion in the room and incomplete combustion. I notice the plants clawing down and yellowing, then I turn the burner off and they come back the next day. Does anyone have any ideas on what could be causing the lack of oxygen??
DunHav`nFun
Well-known member
Ok bro....not much help around here anymore for bigger setups , but you`re in luck since someone repped my post in this 3 yr old thread.....aight....
First off.....If you`re running more than 8-900 ppms of CO2 from your burner then there`s your first x factor.....been proven for awhile that excess ppms are wasted and not needed without increased heat , nutrient uptake for increased metabolism.....Next , your plants live off CO2 not Oxygen , and with 700 sq ft and 9100 cu ft of inherent O2 inside your room to begin with , I`m not sure where your meter readings mean anything as I`ve never known any of my commercial guys to monitor O2 levels since once the plants get big enough they waaaay more than supplement the O2 already inside the room.....now.....if you`re running the CO2 burner during lights off , stop.....the plants eat CO2 during lights on and shit out what they didn't use along with excess water vapor during lights off , so no CO2 needed....
O2 depletion inside the room ?....Maybe I`m missin somethin , dunno.....just can`t see it.....especially with 120000 btu`s of cooling being pumped into the grow area as needed....and.....
Airflow should be beneath the plants being pushed 1 way around the room and airflow above the plants should be pointed the opposite way to provide a vortex of air around but never ON the plants to increase transpiration/sweating that increases nutrient uptake etc, ph imbalances , etc....and yes....you need more wall and floor fans....ok.....
What type setup are you running bro.....What EC are the plants eating .....What`s your VPD/RH percentage wise......What`re light`s on AND lights off temps.....You can`t go wrong with gavitas so all that`s needed is to dial your environment and you`ll be golden.....just remember.....environment means waaaay more than shoving light and nutes up their ass.....anyways.....
Holler back with more info and we`ll see if the problem can`t be figured out further....
Peace.....DHF....
.....
First off.....If you`re running more than 8-900 ppms of CO2 from your burner then there`s your first x factor.....been proven for awhile that excess ppms are wasted and not needed without increased heat , nutrient uptake for increased metabolism.....Next , your plants live off CO2 not Oxygen , and with 700 sq ft and 9100 cu ft of inherent O2 inside your room to begin with , I`m not sure where your meter readings mean anything as I`ve never known any of my commercial guys to monitor O2 levels since once the plants get big enough they waaaay more than supplement the O2 already inside the room.....now.....if you`re running the CO2 burner during lights off , stop.....the plants eat CO2 during lights on and shit out what they didn't use along with excess water vapor during lights off , so no CO2 needed....
O2 depletion inside the room ?....Maybe I`m missin somethin , dunno.....just can`t see it.....especially with 120000 btu`s of cooling being pumped into the grow area as needed....and.....
Airflow should be beneath the plants being pushed 1 way around the room and airflow above the plants should be pointed the opposite way to provide a vortex of air around but never ON the plants to increase transpiration/sweating that increases nutrient uptake etc, ph imbalances , etc....and yes....you need more wall and floor fans....ok.....
What type setup are you running bro.....What EC are the plants eating .....What`s your VPD/RH percentage wise......What`re light`s on AND lights off temps.....You can`t go wrong with gavitas so all that`s needed is to dial your environment and you`ll be golden.....just remember.....environment means waaaay more than shoving light and nutes up their ass.....anyways.....
Holler back with more info and we`ll see if the problem can`t be figured out further....
Peace.....DHF....
.....
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Thanks for replying. The gas is off at night for sure. I have the controller that is set at 900 ppm and only for during day light. I have the sealed room. Air in up high on one side, and air out sucking from the floor on the opposite side. I have 4-16” oscillating fans on the the sides of the room, 2 on each side evenly spaced out. The top of the room has the 2-5 tonne ac units, with a plenum that takes the air up and over to the opposite side and shoots it back towards the acs sonit gets sucked through the plants. I also have 4 floor fans under the canopy at the same side shooting back towards the ac’s. My burner is on the ac side, between the units about 10ft above the floor. I am thinking maybe I should drop it to the ground? This has been so frustrating as I can’t seem to figure it out. I bought a fancy o2, co2, co meter. That at least tells me my o2. I was scratching my head too trying to figure out why my o2 is low. My ladies are 5 weeks in now and not small. They would just be bigger with gas. Thanks for trying to help me out, hopefully we can figure it out.....
Switcher56
Comfortably numb!
Is your burner(8) inside or out? Move it out of the room. Chump change in comparison!
So you mean just take the burner out of the room and not use one?
DunHav`nFun
Well-known member
Well bro.....The CO2 burner`s where it should be since CO2`s heavier than air , and then mixed with cold ac air , one could only assume the colder air would insure the CO2 would drop down amongst the plants as needed for optimum absorption , and I still don`t know your RH , type setup , lights and off temps.....could be a lotta things , but if it`s a DWC or any fast hydro setup , CO2 could be getting to the rootzones in the bottom containers , dunno.....anyways.....
You say you have air coming in and air going out in a sealed room ?.....or is it for air cooled hoods....ok....
Holler back....DHF.....
.....
Bobby Boucher
Active member
I was flamed here awhile back for "propagating" the supposed myth that co2 sinks in a growroom. From what I've read (elsewhere), CO2 only settles the way us pot farmers think it does in completely undisturbed containers, and even then, not quite to the extent that we've been led to believe.
"If left undisturbed, CO2 does sink lower to the ground than oxygen, although they both form separate exponential profiles (it's not like the bottom half of a volume is 100% CO2 while the top half is 100% oxygen - they both have distributions that tail off exponentially with height - it's just that the CO2 /oxygen density ratio is higher at the bottom of a large undisturbed container than at the top)...
Out in the open atmosphere, there is enough motion in the air to keep the oxygen and carbon dioxide mixed up. This motion of the air mostly comes from convection currents (i.e. wind) caused by temperature differences..."
https://physics.stackexchange.com/q...tification-of-partial-pressure-due-to-gravity
"Gases do not separate like oil and water.. After all, gases mix..
But the real question is "how" gases stratify if they don't do so like oil and water. See, oil and water develop this nice boundary line. Gases don't have surface tension, so they will not do this..
..Gases stratify according to an exponential function. The only difference between two gases of different weights is that the rate of decrease with height will be different. So sea-level concentration will favor the heavier gases. High altitudes will favor the light gases. But it is only favoring, they don't totally separate.
The exact argument for why this is the case is rather complicated, but it is covered in the link I gave. The argument is only possible in the first place if we make assumptions that they behave as ideal gases. In the real world, collisions have particular properties along the full energy spectrum that correspond to their molecular shape and their chemical interactions. In that model, it won't be perfectly exponential. In real life, all we can say is that we expect it to look like an exponential, all other things being equal.
Nonetheless, exponential functions that decrease at different rates have a mathematical tendency to diverge dramatically over large enough distances. Because of this, the upper atmosphere is virtually entirely Hydrogen and Helium. But there's no solid boundary where the transition to this happens. That layer is very diffuse and merges gradually with lower layers."
DHF is The Man with The Plan though. I'm just a shit-troll popping his head out from under his shit-bridge to fling some shit around, which in retrospect, now doesn't seem like such a great idea. If ya'll wanna stone me to death, I'll understand, but I already typed this all out so.. I'll just try and accept my fate with a bit of dignity.
"If left undisturbed, CO2 does sink lower to the ground than oxygen, although they both form separate exponential profiles (it's not like the bottom half of a volume is 100% CO2 while the top half is 100% oxygen - they both have distributions that tail off exponentially with height - it's just that the CO2 /oxygen density ratio is higher at the bottom of a large undisturbed container than at the top)...
Out in the open atmosphere, there is enough motion in the air to keep the oxygen and carbon dioxide mixed up. This motion of the air mostly comes from convection currents (i.e. wind) caused by temperature differences..."
https://physics.stackexchange.com/q...tification-of-partial-pressure-due-to-gravity
"Gases do not separate like oil and water.. After all, gases mix..
But the real question is "how" gases stratify if they don't do so like oil and water. See, oil and water develop this nice boundary line. Gases don't have surface tension, so they will not do this..
..Gases stratify according to an exponential function. The only difference between two gases of different weights is that the rate of decrease with height will be different. So sea-level concentration will favor the heavier gases. High altitudes will favor the light gases. But it is only favoring, they don't totally separate.
The exact argument for why this is the case is rather complicated, but it is covered in the link I gave. The argument is only possible in the first place if we make assumptions that they behave as ideal gases. In the real world, collisions have particular properties along the full energy spectrum that correspond to their molecular shape and their chemical interactions. In that model, it won't be perfectly exponential. In real life, all we can say is that we expect it to look like an exponential, all other things being equal.
Nonetheless, exponential functions that decrease at different rates have a mathematical tendency to diverge dramatically over large enough distances. Because of this, the upper atmosphere is virtually entirely Hydrogen and Helium. But there's no solid boundary where the transition to this happens. That layer is very diffuse and merges gradually with lower layers."
DHF is The Man with The Plan though. I'm just a shit-troll popping his head out from under his shit-bridge to fling some shit around, which in retrospect, now doesn't seem like such a great idea. If ya'll wanna stone me to death, I'll understand, but I already typed this all out so.. I'll just try and accept my fate with a bit of dignity.
Well bro.....The CO2 burner`s where it should be since CO2`s heavier than air , and then mixed with cold ac air , one could only assume the colder air would insure the CO2 would drop down amongst the plants as needed for optimum absorption , and I still don`t know your RH , type setup , lights and off temps.....could be a lotta things , but if it`s a DWC or any fast hydro setup , CO2 could be getting to the rootzones in the bottom containers , dunno.....anyways.....
You say you have air coming in and air going out in a sealed room ?.....or is it for air cooled hoods....ok....
Holler back....DHF.....
The RH is 65%, the dehumidifiers are getting installed tomorrow. Yes air in and out wasninstalled as a safety net just in case the ac’a went down, but now I use the exhaust at night and intake during the day. I am using 10g air pots with a mixture of 60% coco and worm castings, 30% pro mix, and 10% perlite. I just moved my floor fans to the ac side under the burner to blow the air underneath the canopy towards the main air movement blowing back above the canopy. For lights I have 20 double ended gavitas, the off temp is set at 90. My rooms run around 79-80. Night temp 72. So weird as I have 2 exact rooms running right now, but one is 18.7 o2 level and the other is 18.0, and it even dipped to 17.8 when I turned the burner on today. All controllers and thermostats are hanging in the middle of the room at canopy height.
Shmavis
Being-in-the-world
I am confused. You say this:
but then proceed to argue otherwise... I agree with the points about stratification relative to conditions. I mean stratification in a garden is rarely an objective, at least not mine... but I feel like I missed something here, maybe the flaming? If you are arguing against definable stratification outside an undisturbed container, why would you propagate a "supposed myth" of stratification? Or are you arguing that it's not a myth, and that CO2 sinks, because it's heavier? Or is that just a myth instead of a supposed one?
[I'm either high or confused]
but then proceed to argue otherwise... I agree with the points about stratification relative to conditions. I mean stratification in a garden is rarely an objective, at least not mine... but I feel like I missed something here, maybe the flaming? If you are arguing against definable stratification outside an undisturbed container, why would you propagate a "supposed myth" of stratification? Or are you arguing that it's not a myth, and that CO2 sinks, because it's heavier? Or is that just a myth instead of a supposed one?
[I'm either high or confused]
Bobby Boucher
Active member
I am confused. You say this:
but then proceed to argue otherwise... I agree with the points about stratification relative to conditions. I mean stratification in a garden is rarely an objective, at least not mine... but I feel like I missed something here, maybe the flaming? If you are arguing against definable stratification outside an undisturbed container, why would you propagate a "supposed myth" of stratification? Or are you arguing that it's not a myth, and that CO2 sinks, because it's heavier? Or is that just a myth instead of a supposed one?
[I'm either high or confused]
My brain still feels hurty from a poor nights rest.. but my argument is that if there is enough air movement in a grow room to keep the plants healthy from the get go, burner/AC/fan placement shouldn't be of any concern, at least not in regards to trying to direct co2 to the plants, well, asides from maybe not placing your burner right next to your exhaust.. ?
CO2 is heavier than O2, but this is really only even noteworthy on a much bigger scale, like in a big corn silo, or a planet's atmosphere. We have to assume that since neither gas has surface tension, that they mix thoroughly in very short order in any room that doesn't have extremely tall ceilings or wasn't completely still and airtight, and even then, it wouldn't be long before the gasses mixed, because.. that's what gases do. Add all the fans we use in a grow room to the equation with only 8-30' of typical headspace in a grow, and you've got an industrial strength OP'ed CO2/O2 blender.
This is just what my feeble little mind has drawn from the material, and I don't really lerm s'good. So.. I'll digest..
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