Co2 for 4x8

Offmymeds

Well-Known Member
Can I get a reason or 2 for why not
I tried it twice. Not worth the trouble unless you have a very tightly controlled environment. You have to keep the temps and humidity stable with no ventilation. Then you need a CO2 monitor and a method to release it. I used a timer with a very low stream of CO2. You also add potential problems like a leaking gasket, timer malfunction, accidental adjustments, etc.

Time & $ spent on better things.
 
Yeah I've been trying to research and figure out the same thing as you, seemed to run into a lot of people dogging it and not too much in terms of actual results.

So I couldn't help it and bought a 20 lb tank, controller/monitor and regulator. Still waiting on the regulator to show up but for a few days now have been adding a little co2 and keeping the tent sealed with a small space heater and humidifier except at night I have a 6" fan come on and a piece of duct running out the top of the tent that I unplug before bed so I have a passive intake.
Young vegging plants. Growth has been crazy though past couple days since I sealed up the tent. Running 82 to 84 degrees steady and between 63 and 70 percent humidity. I've been cracking the tank quick for a second then sealing the tent up and it jumps up to about 1400 ppm and takes maybe
4 or 5 hours to get down around 500ppm where I crack it again.
Running a couple hlg 600r spec in my 4x8, only have one running at 550watts right now though which is why I'm also running a heater. Temps will be perfect once I have both lights going, and should eventually have to switch from humidifier to dehumidifier as the canopy fills.
Pretty excited to see how this goes. I'm normally pumping mountains of air through my 4x8 with a 10inch hyper fan(dialed down a bit). But being winter right now, if I run exhaust with my leds I'm getting temps of 66 to 68(start of a new grow, only running 1 of the 2 led's) with no hope of holding heat with a space heater and rh of 16% unless I drape wet towels across half the tent then I can get rh up but still with cold temps. Steaming humidifier plugs up carbon filter so can't use that with air exchange. Super slow growth with that environment and air exchange method. Started to switch it up like 4 days ago and so happy I did.
CO2 and sealed 5 out of 5 stars, recommend
 

Exotic Reggie

Well-Known Member
I tried it twice. Not worth the trouble unless you have a very tightly controlled environment. You have to keep the temps and humidity stable with no ventilation. Then you need a CO2 monitor and a method to release it. I used a timer with a very low stream of CO2. You also add potential problems like a leaking gasket, timer malfunction, accidental adjustments, etc.

Time & $ spent on better things.
Thanks for the help
 

Exotic Reggie

Well-Known Member
Yeah I've been trying to research and figure out the same thing as you, seemed to run into a lot of people dogging it and not too much in terms of actual results.

So I couldn't help it and bought a 20 lb tank, controller/monitor and regulator. Still waiting on the regulator to show up but for a few days now have been adding a little co2 and keeping the tent sealed with a small space heater and humidifier except at night I have a 6" fan come on and a piece of duct running out the top of the tent that I unplug before bed so I have a passive intake.
Young vegging plants. Growth has been crazy though past couple days since I sealed up the tent. Running 82 to 84 degrees steady and between 63 and 70 percent humidity. I've been cracking the tank quick for a second then sealing the tent up and it jumps up to about 1400 ppm and takes maybe
4 or 5 hours to get down around 500ppm where I crack it again.
Running a couple hlg 600r spec in my 4x8, only have one running at 550watts right now though which is why I'm also running a heater. Temps will be perfect once I have both lights going, and should eventually have to switch from humidifier to dehumidifier as the canopy fills.
Pretty excited to see how this goes. I'm normally pumping mountains of air through my 4x8 with a 10inch hyper fan(dialed down a bit). But being winter right now, if I run exhaust with my leds I'm getting temps of 66 to 68(start of a new grow, only running 1 of the 2 led's) with no hope of holding heat with a space heater and rh of 16% unless I drape wet towels across half the tent then I can get rh up but still with cold temps. Steaming humidifier plugs up carbon filter so can't use that with air exchange. Super slow growth with that environment and air exchange method. Started to switch it up like 4 days ago and so happy I did.
CO2 and sealed 5 out of 5 stars, recommend
I have the 2 optic 650s and es thinking of co2 to get the most out of these leds... thanks for your help
 
I have the 2 optic 650s and es thinking of co2 to get the most out of these leds... thanks for your help
Yeah honestly what's most important if you're gonna run CO2 is being able to have the right environment for it. So running proper VPD and stronger ppfd readings and also keeing a stable environment without big fluctuations in temp/rh is what's going to let the plant be able to take in and utilize that extra co2 in the air.
So depending on how easy it is to keep a healthy controlled environment is if it's worth it for you. Ofcoarse you don't want a bunch of leaks and to be going through co2 like crazy too so it's important to seal up every crack you can on the tent.

Also if you ask me, having a co2 meter/controller that you can plug your regulator into(rather than just plugging the reg into a timer) is almost a must. With that I can just set my ppm to what I want and it will automatically keep it there throughout the day. If you plug into a timer and just have your regulator barely cracked open, you either waste a bunch of time getting ppms built up to high level, probably hours, or you have it cracked open a little heavier so it doesnt take hours to be at 900 or 1100 ppm BUT now your levels will be getting too high inside the sealed tent from building too quickly. Unless you contantly monitor it. Sounds like a pain to me. Not to mention any time you have to open the door to the tent, it'll take time again to build back up.
But, plugged into the controller I can have the valve wider open so that it climbs to the level I want quickly and when it gets to my max set level will automatically shut off until it reaches the minimum preset and turns on again.
Anyhow that's my take on it. Good luck to ya
 

Exotic Reggie

Well-Known Member
Yeah honestly what's most important if you're gonna run CO2 is being able to have the right environment for it. So running proper VPD and stronger ppfd readings and also keeing a stable environment without big fluctuations in temp/rh is what's going to let the plant be able to take in and utilize that extra co2 in the air.
So depending on how easy it is to keep a healthy controlled environment is if it's worth it for you. Ofcoarse you don't want a bunch of leaks and to be going through co2 like crazy too so it's important to seal up every crack you can on the tent.

Also if you ask me, having a co2 meter/controller that you can plug your regulator into(rather than just plugging the reg into a timer) is almost a must. With that I can just set my ppm to what I want and it will automatically keep it there throughout the day. If you plug into a timer and just have your regulator barely cracked open, you either waste a bunch of time getting ppms built up to high level, probably hours, or you have it cracked open a little heavier so it doesnt take hours to be at 900 or 1100 ppm BUT now your levels will be getting too high inside the sealed tent from building too quickly. Unless you contantly monitor it. Sounds like a pain to me. Not to mention any time you have to open the door to the tent, it'll take time again to build back up.
But, plugged into the controller I can have the valve wider open so that it climbs to the level I want quickly and when it gets to my max set level will automatically shut off until it reaches the minimum preset and turns on again.
Anyhow that's my take on it. Good luck to ya
Thanks will keep this in mind
 

Exotic Reggie

Well-Known Member
You're welcome. If it isn't too expensive to ship I'd be happy to give you my CO2 tank and monitor to experiment.

BTW, I've heard the simple CO2 bags work well.
Thanks I've tried a bag on my1st grow and they came out nice my 2nd was without &it was a lot of larf so that's y I'm thinking of going back to co2
 
S
Thanks will keep this in mind
So whatd you end up deciding? I don't know why people dog co2 so much when it comes to tents. The environment does have to be steady and dialed to proper VPD but that's not hard for most people to do unless they're beginners, in which case they should learn to grow without co2 first. Not to mention I find a sealed environment easier to control than an environment with air exchange.
So anyway I just wanted to give you an update on how it's going for me since I'm in a 4x8. I've had my tank going on a controller now for 4 days keeping between 775 and 875 ppms during the 18 hours of lights on and growth has been great and on top of that the needle doesn't even look like it's moved from full yet. Sitting at about 800 psi which is about where the 20 lb tanks come. And I exhaust my tent during lights out. So the old saying you've heard about it being a waste to use in tents is debunked. It's looking like this tank may last me well over a month, possibly up to 2. Waiting for the needle to start moving so I can do the math.
And lastly, about the comment that I read saying "dumping it into your home is a bad idea", its a 4x8 tent. And it's sealed, even despite likely small leaks through zippers and what not it's in no way dangerous when ran how it's suppose to be. It's harmful to humans at 4000ppm, putting 800 to 1100 ppm into a sealed 4x8 is nothing. My main level has much higher levels of ppm between a couple people, dogs and cats than my basement gets with my grow tent and added co2.
 

Exotic Reggie

Well-Known Member
S
So whatd you end up deciding? I don't know why people dog co2 so much when it comes to tents. The environment does have to be steady and dialed to proper VPD but that's not hard for most people to do unless they're beginners, in which case they should learn to grow without co2 first. Not to mention I find a sealed environment easier to control than an environment with air exchange.
So anyway I just wanted to give you an update on how it's going for me since I'm in a 4x8. I've had my tank going on a controller now for 4 days keeping between 775 and 875 ppms during the 18 hours of lights on and growth has been great and on top of that the needle doesn't even look like it's moved from full yet. Sitting at about 800 psi which is about where the 20 lb tanks come. And I exhaust my tent during lights out. So the old saying you've heard about it being a waste to use in tents is debunked. It's looking like this tank may last me well over a month, possibly up to 2. Waiting for the needle to start moving so I can do the math.
And lastly, about the comment that I read saying "dumping it into your home is a bad idea", its a 4x8 tent. And it's sealed, even despite likely small leaks through zippers and what not it's in no way dangerous when ran how it's suppose to be. It's harmful to humans at 4000ppm, putting 800 to 1100 ppm into a sealed 4x8 is nothing. My main level has much higher levels of ppm between a couple people, dogs and cats than my basement gets with my grow tent and added co2.
I appreciate you taking the time to respond I'm going to give it a go just waiting for the clones since this tent is exploding without it20220208_035344.jpg20220208_035348.jpg
 

calvin.m16

Well-Known Member
As long as you're not venting the room outside then you can just run a co2 generator in the same room as the tent. Ignore the rain hoses and shit that's all a scam. I use a Titan Controls Atlas 4 co2 burner to keep my PPMs at 1200-1300 through flower in a 1000 sq/ft area and it keeps the entire room enriched. I spend $30 on propane per/month to run it where with co2 tanks I was spending $30 a week.

Co2 is a heavy gas but as long as you have the air cycling through the tent from the enriched room it will still work. I would look into a tank though unless you have air conditioning in the room the tent is in, co2 burners produce a lot of heat and in your case you'd only need a 2 burner though.. If you plan to go the tank route it will not produce heat like a burner of course but it can be more expensive especially if the room your tent is in isn't really well sealed.

*Always have Carbon Monoxide Detectors in your grow space and sleeping quarters if you plan to go the burner route vs the co2 tank & regulator route, better safe than dead. If it ever malfunctioned just like any gas burning appliance it can release toxic amounts of Carbon Monoxide which is odorless and can kill you.*
 

Shaded420

Well-Known Member
I found this interesting:

Atmospheric CO₂ levels are approximately 370 PPM. Doubling the CO₂ level increases growth by 30%. Reducing CO₂ by one third reduces growth by 50%
If you are recirculating used air back into the grow room the CO₂ levels will reduce and growth rates will slow. With this setup you will have to add CO₂ to the grow room to ensure adequate growth.You will have to use CO₂ meters and a CO₂ generator to your grow room and calibrate it to achieve the desired CO₂ levels and associated growth rates.



Using the naturally higher CO₂ levels in the house to increase growth rate
You can also use your own CO₂. Humans expel CO₂ when breathing out so the level within our homes is often twice the concentration outside. This is most common in winter months when the air circulation in homes is minimal. It's common for CO₂ levels in the home to range from 700 -1,000 PPM. In a bedroom at night CO₂ levels may reach as high as 2,000 PPM. Check out an article here on the CO₂ levels in the typical day of a person at home, work etc. https://www.co2meter.com/blogs/news/co2-levels-at-home

TLDR: if you are growing in your living space you most likely have 2x the required ambient co2 levels just by breathing in your house
 

Milky Weed

Well-Known Member
Ive noticed a real diffrence in growth from last run. Its overall warmer, but i also have it run lights on while i am asleep in my room. The extra co2 definetly is making a difference.

The growth rate is pretty wild once i got everything tuned in. Working on turning up the lights from current 35k lux to atleast 50k. I believe it will be able to handle it this time.

I cant really believe how much water they drink this time around, i had to setup a dehuey in my room and im dumping a few gallons of water out of it every day.
 
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