Big question about Co2....Need Expert on this one Pls !!!!!

My friend has always used Co2 for his grow rooms with the fresh air fans going on for only 30 mins once every 3 hours ( note that he has a considerable size operation ). Lately he has converted to growing vertically and he's noticed he has a humidity problem which creates Powdery Mildew even when using a dehumidifier .

Since he operates with 2 separate flowering rooms of 12 hrs of light ( one is on while the other is off ), someone suggested him to connect them with a 8 inch tube with a strong fan to circulate the air from one room to the other.

The benefits of doing so are:
-more stable humidity levels through out the day and night which helps prevent mildew
-better control air temp ( as this is also a problem when the lights are off )
-having the room which the lights are off and which the plants are producing co2 supply the room which the lights are on which need co2 !!!!

Do u think that the room which the lights are off can supply a sufficient amount of co2 for the second room ???

He usually runs his rooms with 1200 ppm of co2 !! I'm sure that he'll never get that much from mixing the air from the 2 rooms, but will it be enough ????

Thanks for your time guys !

Yeah he will be good, any additional CO2 in a sealed room is good. The plants would benefit from even 600-800 parts of co2...

Whats his humidity at lights off?

Since both rooms share the same air, will the additional Co2 in the room which the lights are on affect in a negative way the plants in the room which the lights are off ?????????????

He has a regular humidifier meter which show 60% at night, but he recently used a Usb temp/humidity data logger monitor such as the El-usb-2 which was placed close to the vertical rockwool slabs and it showed a level of 70-75 % !!!

I thought you said he had a de-humidifier? Anyway, to your question: no, it won't affect them negatively.

?? plants don't use co2 when lights are out. Moving air between both rooms is a very bad Idea as you can infect both grows in a very short time. Mold is caused by poor air movement and high humity and cool temps at night. Get the humidity down to 50% and start moving air around the bottom of your plants. Short term mix 20% milk with 9 parts water and spray affected areas, there is an enzyme in the milk that kills the mold. Will leave some white spotting residue but it's all good and will protect the plant till you fix the environment.

Thanks Woodsmaneh. I know plants don't use co2 at night , but will it damage them ??

Purplehazin, yes he has a dehumidifier but like I said it's a large operation and it's a vertical grow with rockwool slabs up against the wall with gutters at the bottom and sprayers on top, which I guess creates a lot of humidity

JackRush said:

Thanks Woodsmaneh. I know plants don't use co2 at night , but will it damage them ??

Purplehazin, yes he has a dehumidifier but like I said it's a large operation and it's a vertical grow with rockwool slabs up against the wall with gutters at the bottom and sprayers on top, which I guess creates a lot of humidity

Click to expand...

No it won't, just a waste of Co2 and I can't suggest to strongly "don't connect the rooms". What about bugs get them in one room get them in both, you could lose 2 rooms, anyway if he has a big op he knows better than to do that.

Co2 level is important for the growth of the plant,
Plants intake Co2 in day time and it releves it in the night so too much of anything is not good for the health of the plants.
During flowering the plants intake more level of co2,
the co2 level os some 700ppm. co2 can be produced by just burning natural gas...
Regards..