How long should i run CO2?

CaliMedicated

CaliMedicated

Well-Known Member
i know to run it one after the lights come and have it turn off one hr before the lights go off. but in the mean time, should i have it on for 15mins and then off for 15min and continue that way??

or do i run it continue sly?

any advice would greatly help me, i dont want to over do it. im going to be installing it tomorrow.

Thanks
 
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Quiet420Guy

Active Member
What is the size of your area? What kind of CO2 device do you have? You want the PPM level to be about 1500 ppm. That is releasing 1 cubic foot of CO2 into a 10' x 10' x 8' room.

~Quiet420Guy
 
CaliMedicated

CaliMedicated

Well-Known Member
its 96 cubic feet. i used the co2 calc that is in the indoor growing page. but i want to see how long it should run for with in the 10 hrs that its one. should i have it go on and then off or run it the whole 10 hrs straight.

I know several people run Co2 and im corious to see what people are doing?

i have a 20lb tank, with reg , timer, selinod and flow meter.
 
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techhead420

Well-Known Member
Run CO2 whenever the lights are on. You can cycle it but you have nothing to gain by turning it on one after after the lights are on and turning the CO2 off 1 hour before the lights are off.

Photosynthesis is a continuous process in the presence of light and as long as the stomas off the plant are open, CO2 will be consumed.

In cooler temps I continuously run CO2 at 1500 ppm, the solenoid is controlled by the light timer.
 
CaliMedicated

CaliMedicated

Well-Known Member
thanks ill run it contiue sly, it reads in the hydrofarm manuel to run it one hr after the lights are on and turn off one hr before the lights shut off. it also reads to run it for 15min and then turn off, then run for 15, then turn off and so.

i just wanted to make sure that isnt neccessary. I understand the functionality of the whole set up, and i know it is ran when the lights are on. I just wanted to clear up the 15min thing.

Thanks
 
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techhead420

Well-Known Member
CaliMedicated said:
thanks ill run it contiue sly, it reads in the hydrofarm manuel to run it one hr after the lights are on and turn off one hr before the lights shut off. it also reads to run it for 15min and then turn off, then run for 15, then turn off and so.

i just wanted to make sure that isnt neccessary. I understand the functionality of the whole set up, and i know it is ran when the lights are on. I just wanted to clear up the 15min thing.

Thanks
Click to expand...
I have no idea why hydrofarm would say that. Check out the vid below and you can see how fast photosynthesis/gas exchange kicks in when the lights come on.

YouTube - Photosynthesis under water
 
B

bongrippinbob

Well-Known Member
DO NOT RUN IT CONTINUOUSLY!!!!!

You need to calculate how many cubic ft of co2 you need for your space. Mine cab is right about the same size as yours, about 10cu ft larger. In order to get my co2 up to 1500ppm, I run my flow meter at 2cu ft an hr for 4 min.

If your ppms get up over 2000, it becomes toxic to plants. If you are running it continuously, you will be way above that in no time.

Use a co2 calculator and figure out how long to have your solenoid releasing co2. If you don't have a co2 meter to tell you the ppm of co2 in your cab, I would let it run long enough to get it to 1500ppm, then shut it off. Leave all your exhaust fans off, and only your circulating fans going to move the air around. After about 3hrs of the exhaust being off, kick it on for about 15min to recycle the air in the room.

Doing this, you are only injecting Co2 like 3 or 4 times a day. The plants sit in the cab with all the exhaust off, and only the circulation fans going for 3hrs. You need an A/C to keep your cab cool for this long of a period. Simply having an air cooled light will not achieve this. Then exhaust 15min. After this 15min, your exhaust kicks off again, and your Co2 is turned on for like 3 or 4 min. Then the 3hrs starts over again.

This is how most growers run their Co2, and this how the calculators suggest to use it as well.
 
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techhead420

Well-Known Member
bongrippinbob said:
DO NOT RUN IT CONTINUOUSLY!!!!!

You need to calculate how many cubic ft of co2 you need for your space. Mine cab is right about the same size as yours, about 10cu ft larger. In order to get my co2 up to 1500ppm, I run my flow meter at 2cu ft an hr for 4 min.

If your ppms get up over 2000, it becomes toxic to plants. If you are running it continuously, you will be way above that in no time.

Use a co2 calculator and figure out how long to have your solenoid releasing co2. If you don't have a co2 meter to tell you the ppm of co2 in your cab, I would let it run long enough to get it to 1500ppm, then shut it off. Leave all your exhaust fans off, and only your circulating fans going to move the air around. After about 3hrs of the exhaust being off, kick it on for about 15min to recycle the air in the room.

Doing this, you are only injecting Co2 like 3 or 4 times a day. The plants sit in the cab with all the exhaust off, and only the circulation fans going for 3hrs. You need an A/C to keep your cab cool for this long of a period. Simply having an air cooled light will not achieve this. Then exhaust 15min. After this 15min, your exhaust kicks off again, and your Co2 is turned on for like 3 or 4 min. Then the 3hrs starts over again.

This is how most growers run their Co2, and this how the calculators suggest to use it as well.
Click to expand...
Valid points but it also depends on the size of the chamber. I trickle it and have had no problems what so ever. If you have a small chamber, bring it up to 1500ppm then switch the CO2 off, the CO2 will be consumed in no time.

That being said, you're making valid points.
 
B

bongrippinbob

Well-Known Member
You pretty much need to run A/C to use Co2. It is just one of the expenses you have to deal with. I was trying to get away without using it, and I could only have my exhaust off for like 20min before my temps hit 90 degrees. So my plants were only getting the Co2 for 20min at atime.

I was getting extra growth, but not like I would if I had done it correct. I just cut off my Co2 until the end of this harvest soI can get an A/C unit.

That is the same setup I have. Don't use that timer to run your Co2, get digital one because you will only need it on like 4min. Use that one for your exhaust fans. I was giving my plants 6 injections a day, with 20-30 min of fans off. Like I said, it was working, but the plants were starting to show some heat stress. The A/C is a necessity.

If you are going to use the Co2, make sure you use a Co2 calculator to figure out how long to keep it on for. Most likely it will be like 4min. Just get as many cycles in as you can throughout the day. Most digital timers will do 6 or 7 on/off cycles a day. See how long you can keep your exhaust and intake off before your temps hit like 87 degrees, then have your exhaust come on that much longer after the Co2 starts every time. You will see more growth, but like I said, from experience, I have found that you need an A/C.
 
Chumlie

Chumlie

Well-Known Member
This fella on youtube had the same setup as you Cali. He was in a basement so, and he said his temps were mildly cool and had good airflow. Im guessing his temp was around 75 f. He ran his for an hour each time three times a day. Check it out "Mr. Green"
 
CaliMedicated

CaliMedicated

Well-Known Member
Chumlie said:
This fella on youtube had the same setup as you Cali. He was in a basement so, and he said his temps were mildly cool and had good airflow. Im guessing his temp was around 75 f. He ran his for an hour each time three times a day. Check it out "Mr. Green"
Click to expand...

do you know which video, he has all kinds of stuff
 
CaliMedicated

CaliMedicated

Well-Known Member
i skipped a few videos but for th emost part i watched them all. it said on the last video that one thing he checks is his co2, that it runs 15-1 hr for 3 times a day.
 
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bongrippinbob

Well-Known Member
I bet when he is talking about the Co2 is on for 15min-1hr, he means that the exhaust and all that is off for 15min-1hr depending on temps. This would be my guess any way.
 
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stucklikechuck

Well-Known Member
oh and my AC, oscillating fan, scrubber fan are all off during enrichment. the only fan that is on is my sealed fan for the cooltube...
 
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stucklikechuck

Well-Known Member
bongrippinbob said:
DO NOT RUN IT CONTINUOUSLY!!!!!

You need to calculate how many cubic ft of co2 you need for your space. Mine cab is right about the same size as yours, about 10cu ft larger. In order to get my co2 up to 1500ppm, I run my flow meter at 2cu ft an hr for 4 min.

If your ppms get up over 2000, it becomes toxic to plants. If you are running it continuously, you will be way above that in no time.

Use a co2 calculator and figure out how long to have your solenoid releasing co2. If you don't have a co2 meter to tell you the ppm of co2 in your cab, I would let it run long enough to get it to 1500ppm, then shut it off. Leave all your exhaust fans off, and only your circulating fans going to move the air around. After about 3hrs of the exhaust being off, kick it on for about 15min to recycle the air in the room.

Doing this, you are only injecting Co2 like 3 or 4 times a day. The plants sit in the cab with all the exhaust off, and only the circulation fans going for 3hrs. You need an A/C to keep your cab cool for this long of a period. Simply having an air cooled light will not achieve this. Then exhaust 15min. After this 15min, your exhaust kicks off again, and your Co2 is turned on for like 3 or 4 min. Then the 3hrs starts over again.

This is how most growers run their Co2, and this how the calculators suggest to use it as well.
Click to expand...


hey bong,
do you keep your oscillating fans on when co2 is on?
 
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