Sealed Room Co2 At Night/ Need Removing?

  • Thread starter bobby34
  • Start date
  • Tagged users None
P

PharmHand

846
143
Last i checked it was 1600ppm when the lights came on. This was maybe a wk ago
You probably got a better handle on your nighttime humidity than I do. From what I’ve read the plants will release more co2 at night if the humidity is too high. Mine goes 2500+ but it doesn’t seem to hurt them. My monitor shit the bed last run and left the c02 running for like 8hours straight and my ppms went up to 10000. Only a few plants showed some burnt spots similar to cal def
 
G gnome

G gnome

20,448
638
You probably got a better handle on your nighttime humidity than I do. From what I’ve read the plants will release more co2 at night if the humidity is too high. Mine goes 2500+ but it doesn’t seem to hurt them. My monitor shit the bed last run and left the c02 running for like 8hours straight and my ppms went up to 10000. Only a few plants showed some burnt spots similar to cal def
Ive never heard that but my humidity stays in check throughout the dark cycle. No spike at lights out
 
Hookah79

Hookah79

27
3
I’ve seeN that before, maybe not quite that bad. It used to happen every time I’d move plants into my sealed flower room from a vented veg. Were they vegged in there? The sealed room I mean
No they were vegged in a separate room.
But they’ve been also vegging in the flower room for about a month.But my previous 3 runs i’ve vegged them in the same room iam having issues with.
 
Last edited:
P

PharmHand

846
143
No they were vegged in a separate room.
But they’ve been also vegging in the flower room for about a month.But my previous 3 runs i’ve vegged them in the same room iam having issues with.
With the limited details you gave I’d say you probably just introduced too much co2 too fast. Ease them into it. For vegging 6-800ppm max. If you’ve got a lot of light on them in veg stay lower. It looks like they got overloaded with co2 and closed their stomata. When that happens there’s little to no flow of nutrients- water.... calcium which those plants look massively deficient in. Is that promix/peat you’re in?
 
Last edited:
Hookah79

Hookah79

27
3
With the limited details you gave I’d say you probably just introduced too much co2 too fast. Ease them into it. For vegging 6-800ppm max. If you’ve got a lot of light on them in veg stay lower. It looks like they got overloaded with co2 and closed their stomata. When that happens there’s little to no flow of nutrients- water.... calcium which those plants look massively deficient in. Is that promix/peat you’re in?
It’s possible,i run 2 rows of adjustawings with 3 rows of plants under them.The middle row where the they’re right under the wings edge seemed the most effected.I say that because the brightest area comes from the edge of the reflector.It’s possible that with co2 and too much light effected them.I am using jacks nutes topped at 850 ppm ,i did increase it to 950ppm because i have heard nutes uptake increases with co2.Like i said earlier the effected plant’s leaves became really dried and shrivled.Maybe i did start too much early.Maybe i dont have enough humidity either.

The medium iam using is tupur.I am using 400 ppms of jacks to 300 ppms of calnit with 150 tap water.I thought of increasing the calnit a bit more,but again the plants are back where they should without the co2.So iam hoping to figure it out the next run since they’re in flower now.
 
Warrioreuel

Warrioreuel

50
18
I need to add my experience here. My 10x20 (12 ft ceiling) room is totally sealed and sealed tight. I use bottled CO2 with the fuzzy logic Autopilot controller. When I first set the room up my CO2 was all over the place and I was very unhappy with the controller. The problem was i had the valve set so when the CO2 was being released it was coming out full blast, 15 ppm or so, what ever the max setting is on the regulator. The little green ball was all the way at the top of the glass tube. For some reason i thought this was good when i set it up. But, releasing so much CO2 so fast messed up the controller. I dialed the regulator back to a release rate of about 2 ppm and now my CO2 level is dead flat at what ever level I set it. I only run about 500 ppm or so, just making sure my plants never starve. Problem is when I go in the next morning the levels are always about 1500 or so. I bought a separate CO2 monitor that records data (Autopilot APCEM2) (sweet device). You download the data to Excel and graph the results. Like clock work the levels are dead flat at 500 all day then soon as the lights go out is steadily rises to 1500 or so. The lights come on and the level ramps down to 500 and stays there all day like it should. I turned the tank valve completely off and it still rose to 1500. This ruled out any leak or controller malfunction. So whatever the process is my CO2 rises steady all night. Still trying to figure it out. Venting at night seems to be the most likely cure. My guess is that if your CO2 level is not rising at night then maybe your room is not as sealed as you think. I say this because with this newest sealed room my CO2 usage is so much lower than before that I can only conclude my other rooms are not sealed very well. I have 14 very bushy plants with about 3 weeks left before harvest and my CO2 gauge is still almost exactly as when the tank was full. Normally i would replace that tank every 3 or 4 weeks. So my room is sealed tight. Some said something about humidity causing increased CO2. My day and night humidity is too high at about 70%. New dehumidifier comes in next week to solve that problem. It will be interesting to see if the lower humidity affects the CO2 level at night.
 
Last edited:
jumpincactus

jumpincactus

Premium Member
Supporter
11,609
438
I need to add my experience here. My 10x20 (12 ft ceiling) room is totally sealed and sealed tight. I use bottled CO2 with the fuzzy logic Autopilot controller. When I first set the room up my CO2 was all over the place and I was very unhappy with the controller. The problem was i had the valve set so when the CO2 was being released it was coming out full blast, 15 ppm or so, what ever the max setting is on the regulator. The little green ball was all the way at the top of the glass tube. For some reason i thought this was good when i set it up. But, releasing so much CO2 so fast messed up the controller. I dialed the regulator back to a release rate of about 2 ppm and now my CO2 level is dead flat at what ever level I set it. I only run about 500 ppm or so, just making sure my plants never starve. Problem is when I go in the next morning the levels are always about 1500 or so. I bought a separate CO2 monitor that records data (Autopilot APCEM2) (sweet device). You download the data to Excel and graph the results. Like clock work the levels are dead flat at 500 all day then soon as the lights go out is steadily rises to 1500 or so. The lights come on and the level ramps down to 500 and stays there all day like it should. I turned the tank valve completely off and it still rose to 1500. This ruled out any leak or controller malfunction. So whatever the process is my CO2 rises steady all night. Still trying to figure it out. Venting at night seems to be the most likely cure. My guess is that if your CO2 level is not rising at night then maybe your room is not as sealed as you think. I say this because with this newest sealed room my CO2 usage is so much lower than before that I can only conclude my other rooms are not sealed very well. I have 14 very bushy plants with about 3 weeks left before harvest and my CO2 gauge is still almost exactly as when the tank was full. Normally i would replace that tank every 3 or 4 weeks. So my room is sealed tight. Some said something about humidity causing increased CO2. My day and night humidity is too high at about 70%. New dehumidifier comes in next week to solve that problem. It will be interesting to see if the lower humidity affects the CO2 level at night.
Pics of those 14 bushes please
 
Warrioreuel

Warrioreuel

50
18
Pics of those 14 bushes please
I should have known better than to tease like that.
Nov 1 2018 Cherry Bomb
 
jumpincactus

jumpincactus

Premium Member
Supporter
11,609
438
very nice man. Good looking space and galz :D:smoking::fire: those Leds your running?
 
Warrioreuel

Warrioreuel

50
18
12 ft ceilings!!!nice!!
Is that a bad thing when it comes to air movement, keeping co2, temps, and rh in check?
First let me say the reason i went to 12 foot ceilings is because when reality sets in with 8 foot ceilings a 3 foot plant is pushing the limit on height. By the time you hang your lights, maintain 24" above the canopy, the buckets i grow in start the plant already 18" from the floor. I got tired of having to always search for the shortest possible strains and then struggle to keep them in check. So the hopes are that with 12 foot ceiling i can grow some sativa strains that like to get tall. The crop you see in there now is the first grow for that room and I already had the seeds which are speced at 90cm height as i recall, so short. Air movement is not a problem. I have a Can 75 filter with a 10" fan standing up in the corner you cant see. I put a single elbow on top so the air shoots out across the room. As you can see also there is a fan on the back wall. Yes, at the moment I am having a humidity overload problem. I am using a 70 ppd and a 40 ppd residential type stand in the corner unit I had laying around. I don't think its the 12 foot ceilings but rather the thick growth of 14 healthy gals. That problem should be cleared up this week as tomorrow I take delivery on a Quest Dual 155. The lighting is 12 x CLW 550W. Best lights I have ever used without a doubt. In fact I have them dialed back to 85% at full light because 100% was just not needed, especially late in the grow like you see now. Just for the record, AC is 36K Daiken unit. I have used Mitsubishi units in the past and right now i can say I prefer the Mits but the Daiken is working fine. The reason I went with Daiken is the included remote control can be programmed for 4 events per day. So i can set my temps to 75 in the day and automatically dial down to 65 at night. The Mits can do this also but the solution is very awkward. You have to buy a Mits programmable wall thermostat and some ridiculous interface box so it can talk to the air handler. Adds an extra $300 to the cost. Keeping my CO2 levels elevated is NO problem. I have a 20 pound tank and it has lasted already way loger than anything in the past. This room is really sealed. In fact it is so sealed I am adding an electrically controlled vent to swap out the air at night to dump excess CO2. For the record the grow you are looking at has exactly 4 weeks left.
 
TerpyTyrone

TerpyTyrone

692
143
Has anyone tried a suspended ceiling? "Drop" tiles? They make drywall coated in white vinyl for kitchens. Its cheaper than conventional fiberglass tile.
I wanna finish my basement and
First let me say the reason i went to 12 foot ceilings is because when reality sets in with 8 foot ceilings a 3 foot plant is pushing the limit on height. By the time you hang your lights, maintain 24" above the canopy, the buckets i grow in start the plant already 18" from the floor. I got tired of having to always search for the shortest possible strains and then struggle to keep them in check. So the hopes are that with 12 foot ceiling i can grow some sativa strains that like to get tall. The crop you see in there now is the first grow for that room and I already had the seeds which are speced at 90cm height as i recall, so short. Air movement is not a problem. I have a Can 75 filter with a 10" fan standing up in the corner you cant see. I put a single elbow on top so the air shoots out across the room. As you can see also there is a fan on the back wall. Yes, at the moment I am having a humidity overload problem. I am using a 70 ppd and a 40 ppd residential type stand in the corner unit I had laying around. I don't think its the 12 foot ceilings but rather the thick growth of 14 healthy gals. That problem should be cleared up this week as tomorrow I take delivery on a Quest Dual 155. The lighting is 12 x CLW 550W. Best lights I have ever used without a doubt. In fact I have them dialed back to 85% at full light because 100% was just not needed, especially late in the grow like you see now. Just for the record, AC is 36K Daiken unit. I have used Mitsubishi units in the past and right now i can say I prefer the Mits but the Daiken is working fine. The reason I went with Daiken is the included remote control can be programmed for 4 events per day. So i can set my temps to 75 in the day and automatically dial down to 65 at night. The Mits can do this also but the solution is very awkward. You have to buy a Mits programmable wall thermostat and some ridiculous interface box so it can talk to the air handler. Adds an extra $300 to the cost. Keeping my CO2 levels elevated is NO problem. I have a 20 pound tank and it has lasted already way loger than anything in the past. This room is really sealed. In fact it is so sealed I am adding an electrically controlled vent to swap out the air at night to dump excess CO2. For the record the grow you are looking at has exactly 4 weeks left.
Excellent. Just planning my room 2.0 in my future, forever home. As far as exchange rates, lights, a.c. good analysis. I respect a well thought out and easily read reply! Cheers
 
Warrioreuel

Warrioreuel

50
18
Originally this post was discussing rising CO2 levels at night. I had the same problem so joined in the talks. It was suggested that high humidity contributed to the release of CO2 at night hours. My humidity was too high in general and just yesterday I upgraded to a Quest Dual 155. Pulled the room down to 50% in no time. Early this morning I peeked inside and the CO2 was at 1500 ppm up from my normal daytime levels of 500. So right now I am saying "high" humidity has nothing to do with CO2 rising at night hours. Its only been a 1 day test and I will continue to monitor the results and report otherwise if they change. Next test is to remove the entire CO2 tank from the room tonight. I checked it for leaks with soap but maybe i missed something.
 
L

LazyVsLLC

4
3
bobby i been running sealed rooms exclusively for a long long time and you FOR SURE need to pump in fresh air into your room during the plants night cycle..... you can try and extract it as well but i would pump in fresh air... if your in a cold area this can be tricky in the winter cuz ur room will get too cold.... IF you dont pull in fresh air your co2 in ur room at night could be up as high as 1200 ppm which fucks up ripening and WILL Negativley effect your quality smell and all that shit
 
L

LazyVsLLC

4
3
Bobby:
You seem to know your shit:
Believe it or don't but I am roughly eight days away from harvesting roughly 580+- ladies of fairly good bud
I have NEVER done this kinda volume b4 & am kinda freakin, I am in a legal state if that matters. I have a nice trim pro trimmer but have come to the realization recently that I am going have to dry trim (which I have never done) ...just hired a guy & directing me what to do.
Building drying rooms now (like at the moment) understand that I am going to have to have the ability to control humidity and even more so temperature. Furthermore: Need to keep temp & humidity slowly changing for a week or temps 50-to 60 until stems at 16%. (I may be misquoting numbers, but you get my drift. For planning/building we are planning 1 plant hung upside down, stem cut at bottom of canopy (we were in grow way too long so were way to tall initially so if we included roots this time we probably would not have room for two high & thus not enough room in our planned area for all that coming so we would be screwed anyways.
Whatever you or ANYONE else could chime in with would be GREATLY appreciated.
Ken
 
Last edited:
weedtech

weedtech

Supporter
419
93
There is an explanation for a slight increase in CO2 levels during the dark period in a totally closed environment. This is the Krebs Cycle (cellular respiration) at a time when carbon cannot be fixed in the light dependent Calvin Cycle.


I can see this effect in my tent, since I always monitor the CO2 levels.
 
Aqua Man

Aqua Man

26,480
638
There is an explanation for a slight increase in CO2 levels during the dark period in a totally closed environment. This is the Krebs Cycle (cellular respiration) at a time when carbon cannot be fixed in the light dependent Calvin Cycle.


I can see this effect in my tent, since I always monitor the CO2 levels.
Yep my night time CO2 will shoot up to 2500. In the first hour that gets eaten up easily.
 
SundaeDriver

SundaeDriver

1
1
I need to add my experience here. My 10x20 (12 ft ceiling) room is totally sealed and sealed tight. I use bottled CO2 with the fuzzy logic Autopilot controller. When I first set the room up my CO2 was all over the place and I was very unhappy with the controller. The problem was i had the valve set so when the CO2 was being released it was coming out full blast, 15 ppm or so, what ever the max setting is on the regulator. The little green ball was all the way at the top of the glass tube. For some reason i thought this was good when i set it up. But, releasing so much CO2 so fast messed up the controller. I dialed the regulator back to a release rate of about 2 ppm and now my CO2 level is dead flat at what ever level I set it. I only run about 500 ppm or so, just making sure my plants never starve. Problem is when I go in the next morning the levels are always about 1500 or so. I bought a separate CO2 monitor that records data (Autopilot APCEM2) (sweet device). You download the data to Excel and graph the results. Like clock work the levels are dead flat at 500 all day then soon as the lights go out is steadily rises to 1500 or so. The lights come on and the level ramps down to 500 and stays there all day like it should. I turned the tank valve completely off and it still rose to 1500. This ruled out any leak or controller malfunction. So whatever the process is my CO2 rises steady all night. Still trying to figure it out. Venting at night seems to be the most likely cure. My guess is that if your CO2 level is not rising at night then maybe your room is not as sealed as you think. I say this because with this newest sealed room my CO2 usage is so much lower than before that I can only conclude my other rooms are not sealed very well. I have 14 very bushy plants with about 3 weeks left before harvest and my CO2 gauge is still almost exactly as when the tank was full. Normally i would replace that tank every 3 or 4 weeks. So my room is sealed tight. Some said something about humidity causing increased CO2. My day and night humidity is too high at about 70%. New dehumidifier comes in next week to solve that problem. It will be interesting to see if the lower humidity affects the CO2 level at night.

what exhaust will you use?
 
Jmaes Mabley

Jmaes Mabley

693
143
Plants dont need CO2 at Lights Out. Best case scenario, you would give them Oxygen, and vent the CO2.
One would determine the appropriate PPM of Air, and use it like CO2 ect

Plants use oxygen when lights are out, and give of CO2, accounting on your CO2 rise when lights are out.
Plants use CO2, and give off oxygen when lights are on.
 
Aqua Man

Aqua Man

26,480
638
Plants dont need CO2 at Lights Out. Best case scenario, you would give them Oxygen, and vent the CO2.
One would determine the appropriate PPM of Air, and use it like CO2 ect

Plants use oxygen when lights are out, and give of CO2, accounting on your CO2 rise when lights are out.
Plants use CO2, and give off oxygen when lights are on.
Kinda... they use oxygen all the time... they just stop producing o2 when no photosynthesis. They produce co2 all the time from respiration. I belive about half of what they uptake during photosynthesis. We don't notice the co2 produced during the day in a sealed room because they are consuming it. When they stop photosynthesizing then respiration continues and we see the co2 build up.
 

Latest posts

Top Bottom