How To Maximize Results In A Sealed Grow Room Environment

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Judaz

Judaz

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There is so many different opinions & arguments regarding the proper way to run a sealed grow room environment for getting the most optimal results and highest yields around the act of exchanging the air in a sealed grow room supplemented with CO2, that I decided to start this thread to share with you what I've learned with all my past experiences and findings in setting up many commercial sealed grow room environments over the last ten years.

To ventilate or Not to ventilate?

Many argue that there is no need to ventilate a sealed grow room environment because you can simply supplement CO2 and scrub the air with a carbon filter. They say it's a waste of money to let excess CO2 escape and that there is no benefit in doing this. Then I ask them how many sealed grow room environments have they've built and it's usually only a few.

The proven benefit of a sealed grow environment is that you can control and really dial in the elements of the environment to achieve better results than a traditional open air exchange system. The general concensus is that you can truly achieve better quality and maximize weight with a sealed grow room setup. But are you truly maximizing your results?

While many claim to achieve good or great results with a completely sealed room with no air exchange, and also never experience any issues with plants my experience has shown me otherwise.

I've setup many sealed rooms the exact same ways where I have achieved great results and other times I've gotten different results using the same exact setup in a different place. This has boggled my mind for years of why this may be happening. Some places I pulled my best grows and yields and others have given me moderately average results to my grow standards. I don't know the reason yet why this happens sometimes but I've come to the conclusion that when you take away what's worked in nature for millions of years and then attempt to fabricate it by adding all the known needed elements to properly grow cannabis correctly you would expect to get the same results but time has shown me that this isn't the quite case. I've seen unexplained plant problems, small nugs, plants getting freakish leaf wilt, plants acting weird for no reason etc with sealed grow rooms that all had one thing in common and there was no air exchange. Wether it's bad gases in the environment, like excess ethylene or drowning your root zone with too much CO2 etc who knows. Let all those arguments continue. What I do know is that ever since I started running hybrid type systems all the freak problems went away and I am achieving the results of what one would consider a master grower.

There is a way of getting better results by running a hybrid of both systems. Taking what already works in nature and combining it with what man has discovered with CO2 enrichment and environment control to form a hybrid system that helps keep the known and unknown important elements of the environment at balance is what I found to be the key for the perfect grow room.

A hybrid room that is sealed With CO2 enrichment and at the same time ventilated with a continous exhaust fan running at a much slower rate usimg a dimmer so I don't suck out all the CO2 in minutes so that I can still maintain the proper levels of all the necessary known and unknown elements in the environment of nature was the key to having all these freak issues go away. After doing this I've never seen these problems crop up again. Even though my CO2 expense goes up a bit my yields have been the best ever. The buds just simply get bigger. Hitting over 3+ pounds a light with gavita fixtures. When I didn't vent my sealed room I would get 2.3-2.5 a light. I learned this from a very experienced grower in the San Fernando valley. He is the guy who created the sfv og strain. This is how he does his sealed rooms and hits 3.5 pounds a light on a consistent basis. Every grower out here in the SFV that hits over 3 a light runs theirsealed rooms like this. The first picture is my top buds from my og kush strain using the hybrid system, the second picture is a top bud of the same og kush strain under a traditional sealed grow room with no air exchange. I still don't know the science of why this occurs but what I do know is my results from my past experiences growing og kush and the secretes of the best growers of the SFV which first put og kush strain on the map and made it famous to the rest of the world.

Any thoughts or similar experiences?
 
How to maximize results in a sealed grow room environment
How to maximize results in a sealed grow room environment 2
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G gnome

G gnome

20,448
638
There is so many different opinions & arguments regarding the proper way to run a sealed grow room environment for getting the most optimal results and highest yields around the act of exchanging the air in a sealed grow room supplemented with CO2, that I decided to start this thread to share with you what I've learned with all my past experiences and findings in setting up many commercial sealed grow room environments over the last ten years.

To ventilate or Not to ventilate?

Many argue that there is no need to ventilate a sealed grow room environment because you can simply supplement CO2 and scrub the air with a carbon filter. They say it's a waste of money to let excess CO2 escape and that there is no benefit in doing this. Then I ask them how many sealed grow room environments have they've built and it's usually only a few.

The proven benefit of a sealed grow environment is that you can control and really dial in the elements of the environment to achieve better results than a traditional open air exchange system. The general concensus is that you can truly achieve better quality and maximize weight with a sealed grow room setup. But are you truly maximizing your results?

While many claim to achieve good or great results with a completely sealed room with no air exchange, and also never experience any issues with plants my experience has shown me otherwise.

I've setup many sealed rooms the exact same ways where I have achieved great results and other times I've gotten different results using the same exact setup in a different place. This has boggled my mind for years of why this may be happening. Some places I pulled my best grows and yields and others have given me moderately average results to my grow standards. I don't know the reason yet why this happens sometimes but I've come to the conclusion that when you take away what's worked in nature for millions of years and then attempt to fabricate it by adding all the known needed elements to properly grow cannabis correctly you would expect to get the same results but time has shown me that this isn't the quite case. I've seen unexplained plant problems, small nugs, plants getting freakish leaf wilt, plants acting weird for no reason etc with sealed grow rooms that all had one thing in common and there was no air exchange. Wether it's bad gases in the environment, like excess ethylene or drowning your root zone with too much CO2 etc who knows. Let all those arguments continue. What I do know is that ever since I started running hybrid type systems all the freak problems went away and I am achieving the results of what one would consider a master grower.

There is a way of getting better results by running a hybrid of both systems. Taking what already works in nature and combining it with what man has discovered with CO2 enrichment and environment control to form a hybrid system that helps keep the known and unknown important elements of the environment at balance is what I found to be the key for the perfect grow room.

A hybrid room that is sealed With CO2 enrichment and at the same time ventilated with a continous exhaust fan running at a much slower rate usimg a dimmer so I don't suck out all the CO2 in minutes so that I can still maintain the proper levels of all the necessary known and unknown elements in the environment of nature was the key to having all these freak issues go away. After doing this I've never seen these problems crop up again. Even though my CO2 expense goes up a bit my yields have been the best ever. The buds just simply get bigger. Hitting over 3+ pounds a light with gavita fixtures. When I didn't vent my sealed room I would get 2.3-2.5 a light. I learned this from a very experienced grower in the San Fernando valley. He is the guy who created the sfv og strain. This is how he does his sealed rooms and hits 3.5 pounds a light on a consistent basis. Every grower out here in the SFV that hits over 3 a light runs theirsealed rooms like this. The first picture is my top buds from my og kush strain using the hybrid system, the second picture is a top bud of the same og kush strain under a traditional sealed grow room with no air exchange. I still don't know the science of why this occurs but what I do know is my results from my past experiences growing og kush and the secretes of the best growers of the SFV which first put og kush strain on the map and made it famous to the rest of the world.

Any thoughts or similar experiences?
Great thread idea!!!

Ive had this conversation many times b4 and have ran my rm both ways "hybrid" (as u call it) and completely sealed. Ive built more grow rms than i care to admit lol....tried it both ways and must say.....i havent noticed a difference. .....that being sed as a precautionary measure the next groom i put together (next month) will have an exaust system. Fwiw i use a propane fueled co2 generator.
I must also say my personal best yield ever (4# per) was in a semi sealed rm where i had an exaust on a timer than ran for 10min every 4hrs. I did this more for scent control than anything else. the amount of co2 lost when ventilating in such a way is negligible so my rationale is why not run the exaust and avoid the potential build up of ethylene. Not to mention its easier to control the smell w a lil negative pressure.
 
Judaz

Judaz

476
93
Great thread idea!!!

Ive had this conversation many times b4 and have ran my rm both ways "hybrid" (as u call it) and completely sealed. Ive built more grow rms than i care to admit lol....tried it both ways and must say.....i havent noticed a difference. .....that being sed as a precautionary measure the next groom i put together (next month) will have an exaust system. Fwiw i use a propane fueled co2 generator.
I must also say my personal best yield ever (4# per) was in a semi sealed rm where i had an exaust on a timer than ran for 10min every 4hrs. I did this more for scent control than anything else. the amount of co2 lost when ventilating in such a way is negligible so my rationale is why not run the exaust and avoid the potential build up of ethylene. Not to mention its easier to control the smell w a lil negative pressure.

I totally agree. The extra CO2 cost is negligible given the positive results. I think strains also play a big role. Some more sensitive than others. Water quality and the time and way you feed them too. The next room I'm building im trying something my buddy did that has helped him manage his rooms when it's too hot or when it's too humid outdoors when using this hybrid system exhaust and fresh air intake with hepa filter. He placed the intake of fresh air right next to the intake of intake of the 5 ton split ac unit he is using. This way if the outside air is warm or humid it first passes through the ac unit and gets dehumidified and cooled in the process before hitting the canopy
 
DemonTrich

DemonTrich

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How would exhausting co2 that you pay for, and what your plants need at light on benefit in any way? All tour doing is exhausting co2 air out, then your reg opens back up and refills the room.

My room only gets air exchanges when I open and close the door. That's it.
 
G gnome

G gnome

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I am lost on the benefits of exhausting. For what reason are you exhausting CO2 and at what PPM are you dumping it?
Its not a matter of ppm u reach when u exhaust. The idea is to not let the ethylene build up in the rm.

I cant say i fully understand it either but again my rationale is it aint hurting nothin to exchange the air occasionally. ... unlesd like demon ur usin bottles which is a lot more expensive than a co2 generator.
 
Homesteader

Homesteader

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Well I run a different form of hybrid system which uses soil respiration for CO2 until the plants get too large and consume too much gas and then it starts tapping from my bottle.
I think introducing more fresh air into the room would negate the protections that come with a sealed room that prevents airborne mold, pests and pathogens.
I don't know about ethylene but I would be interested in being able to track my ammonia levels because it probably is high at certain points in my grow and I bet it slows growth.
 
Judaz

Judaz

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93
I am lost on the benefits of exhausting. For what reason are you exhausting CO2 and at what PPM are you dumping it?

Theoretically you shouldn't have to but experience has proven otherwise for me. Especially when running burners that use propane. Sometimes sealed rooms give issues and venting it out has seemed to fix many issues. For example on this thread a grower talks about phantom problems in sealed grow rooms and it was fixed by exchanging fresh air https://www.thcfarmer.com/community...es-leaf-necrosis-offgassing-outgassing.45767/

The point that I'm trying to make is that my best results have come from hybrid systems and not sealed grow rooms alone
 
Judaz

Judaz

476
93
I am lost on the benefits of exhausting. For what reason are you exhausting CO2 and at what PPM are you dumping it?

I use an igs-061 controller to manage the ppm levels. It's not that my CO2 levels reach a certain ppm number then I dump it out. I've created a small continous air flow that exchanges air 24/7 but my controller keeps the ppm at the level I set it at. Think of a sealed grow room that has a small leak that creates negative pressure. I'm using a fan dimmer to slowly exchange the air and at the same time I'm able to maintain my desired CO2 ppm levels. Yes I'm wasting a bit more CO2 this way and running my gas expense up but the added pounds that I get make up for that extra little expense.
 
Judaz

Judaz

476
93
Well I run a different form of hybrid system which uses soil respiration for CO2 until the plants get too large and consume too much gas and then it starts tapping from my bottle.
I think introducing more fresh air into the room would negate the protections that come with a sealed room that prevents airborne mold, pests and pathogens.
I don't know about ethylene but I would be interested in being able to track my ammonia levels because it probably is high at certain points in my grow and I bet it slows growth.

I'm using a hepa filter, to filter the fresh air and the next thing that I will do is run a duct from my fresh air intake and put it right next to the intake of my ac. Since I'm using a 2 way split AC system it circulates the air in the room and cools it down and also removes humidity. By putting the small fresh air intake flow next to my AC intake, this will cool down and dehumidify outside air that might be hot or humid from a day with bad weather instead of dumping that hot and or humid air on my plants, I will pass it through the AC system first.

"GrowBright high-efficiency particulate arrestance (HEPA) filters remove 99.97% of airborne particles 3 micrometers or smaller to prevent insects and other particulates such as dust, mold spores, and pollen from entering grow tents or grow roomsthrough the ventilation system."
 
Freshone

Freshone

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I agree sealed rooms are problematic and a little fresh air seems to enrich the environment but I don't like dumping the bought air(ac)and the bought co2(bottled in my case)out after I just paid put it in.Alot of people vent at night a few times or every few hours but constantly at a very low rate seems like you would burn through co2.
How much air are you leaking and what's your intake and exhaust setup?how large are your vents,how many cfm fan/s?
 
Judaz

Judaz

476
93
I agree sealed rooms are problematic and a little fresh air seems to enrich the environment but I don't like dumping the bought air(ac)and the bought co2(bottled in my case)out after I just paid put it in.Alot of people vent at night a few times or every few hours but constantly at a very low rate seems like you would burn through co2.
How much air are you leaking and what's your intake and exhaust setup?how large are your vents,how many cfm fan/s?

I have 20x20x10 cubic ft room when you use the formula to calculate how many cfm this would equate to you multiply the cubic feet by 1.33 which comes out to 5320 cfm. I use 2 400 cfm active air fan with 2 active air dimmer running the exhaust fan speed at 5% and the intake fan speed right around 3-4 %to give me a little neg pressure. 5320/20 Approx 4.5 hours to clear the whole room.
 
Freshone

Freshone

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And this runs 24/7?
Burner or bottle?trying to wrap my mind around how much gas this would use constantly venting.My enviro is also either very cold or very very hot so my split would run constantly.
 
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Judaz

Judaz

476
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And this runs 24/7?
Burner or bottle?trying to wrap my mind around how much gas this would use constantly venting.My enviro is also either very cold or very very hot so my split would run constantly.

First of all let me ask you a few questions. Where do you live? What max and min temperatures are you experiencing normally in your area. Also what strain are you running and what are your avg yields you are getting. You maybe ok with what you are doing. I run og kush and my strain is specifically very finicky so this works for my strain. Others I know dump the air out a couple times during the day cycle and run it consistently during off cycle but the temps in my area are not extreme.
 
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Judaz

Judaz

476
93
I follow Kevin Stark on LinkedIn and he puts it well. He is a indoor farming climate control specialist. When designing your room you must consider the strain you are growing. These small tweaks to sealed grow rooms are strain dependent. Micro climates play a big role in strains.

"Technology has caused a storm of excitement when it pertains to controlled atmospheric growing environments (CAGE). The ability to dial in your CAGE, even compared to 10 years ago, means your grow room can sustain environmental conditions anywhere between Northern California and Thailand.

Although all CAGE will use the same equipment to maintain control, when designing your grow room, the process begins by learning what your plant’s environmental set-point is. This is important because if your focus is on growing sativas, like a Thai varietal that has adapted to humid, sweltering conditions, then maintaining 65 degrees and 30% humidity will not make the plants happy.

So when you’re in the design phase of your operation, kick-start the whole HVAC conversation by first determining what environmental conditions need to be achieved. Deciding on the number of varietals to grow makes this process more straight forward. One option more growers are taking is designing individual flowering rooms or whole greenhouses dedicated to one strain or one environmental set-point. Doing this reduces the complications of making multiple varietals happy in one space. It also reduces the resources needed to condition different areas of one grow facility. This philosophy will apply particularly to the drying and curing areas, but also to the cloning chamber, vegetative and flowering rooms. All these individual environments will require different mechanical inputs to achieve the desired results."

https://www.linkedin.com/pulse/take-control-your-grow-operation-kevin-stark

http://cannabisclimatesolutions.com/
 
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