I have 2 plants in a bed room that is 80%used for storage so the grow area is about 4 foot x 10 foot. I was thinking of experimenting with adding a trickle of Co2. So i bought a co2 meter before hand to see where im at expecting 400-800 but the room is at 1127ppm. Im confused as to why its so high and is it high enough ive been told 1400ppm is best? Could the plants be creating the 1127 at night now that they are breathing oxegen at night?
3 Likes
Plants breathe CO2 and expel oxygen. I would have your HVAC system checked out if your CO2 is that high, as it is most likely present in other spaces than just your grow space.
The use of supplemental CO2 requires intense lighting (1,200+ PPFD) and a well-controlled environment. Elevated CO2 is otherwise a waste of time and money, as the plant cannot utilize the extra CO2 if the plant is not in a properly controlled environment.
Be aware that chronically high CO2 in your living space can be dangerous. A former member of this forum lost a friend to CO2 poisoning from a grow room. That said, it will take more than 1,127 PPM to harm you more than perhaps feeling a little strange.
7 Likes
Just got the meter today so i do plan to check other areas though out the house. I read that as the plants flowers though the dark 12 it reversed from co2 intake to oxygen which would in return expel co2 ?
Plants transpire moisture (humidity) via the leaves at night, but it’s always CO2 in and O2 out.
Roots do need oxygen, but not a lot. If in soil, wet/dry cycles between waterings is sufficient to see that roots get the oxygen they need.
3 Likes
Thanks!!
1 Like
Ambient co² is typically around 400ppm. Merely being in a room talking, working, or whatever will elevate the co² levels. Pets can/will do this too. If you’re also supplementing co² in other ways this level wouldn’t be unheard of, but I agree with checking just to be safe.
3 Likes
That lil heater next to your plant may well be producing Co2. Also if you have gas appliances like a hot water tank near by it’s definitely producing! Allot of growers will intentionally park a tent near by gas appliance for the added co2 
3 Likes
The first thing that I would do, is take the meter outside to check if it is reading correctly. I know the percentage of CO2 in the air, but not sure what ppm would be. You may need to research this first. I have learned not to trust any meter unless it can be verified accurate.
4 Likes
So after a day or so moving the meter around the house most areas are around 5-600. We do have 2 pets in the house and 3 adults. After leaving the meter alone for a day or so in the room its averaging 800-850. HVAC system in not on. But seem like every time its moved it sky rockets and takes hours to settled down again. 
going to monitor for a few more days before adding Co2 to the room.
Normal ambient CO2 is 400 to 500 PPM.
1 Like
@Firstauto
@MidwestGuy knows this, the picture (s) addition is for you.
Dr Bruce Bugbee, USU Guru would probably agree.
Got these off YT while reading/browsing.
Good growing to you, all.
1 Like
Dave thank you for the info
This is what i have for each plant but per the info CO2 still not in the game.
1 Like
Dave if you don’t mind another question i would ask if i have 1 @ 208w light producing 893 PPFD if i linked 2 of the lights together would i have 416w and 1783 PPFD OR would i still only have 208w 893 PPFD being able to cover a bigger foot print.
Two lights = more better coverage.
Not necessarily, double PPDF, just better all around coverage.
I use UT383-BT meter for mapping. Android phone suxked for process.
Hand held meter works BlueTooth and capture software.
Best for answering your question.
Both lights, on reduced output setting as summer heat battle continues.
4x4 tent
1 Like