When to Stop co2 Increase During Flowering?
- Thread starter Micobfsb
- Start date
DirtyEyeball696
Well-Known Member
Ok got a question what is a good temp to maintain 45-50% humidity consistently
I'm noticing when the lights go off it seems to rise. I have my temp set at 73 when they go off. Should I raise it to 75 maybe?
Kush Is My Cologne
I'm noticing when the lights go off it seems to rise. I have my temp set at 73 when they go off. Should I raise it to 75 maybe?
Kush Is My Cologne
organixx325
Active Member
I think your best bet would be to add a dehumidifier or at least some ventilation to move the air around at night.
DirtyEyeball696
Well-Known Member
I have 2 Aprilaire 90 pint a day. Everything seems ok until the lights go off and it seems to raise so I was wondering if I raised my "lights off" temp it might make my dehumidifiers. Maybe 75 degrees.
Kush Is My Cologne
Kush Is My Cologne
Rasta Roy
Well-Known Member
Exhaust that air out of your room when your lights click off fam!
Rasta Roy
Well-Known Member
You're the man for that post. Co2 use (like everything in the cannabis community) is full of misinformation even though there's good information out there.
DirtyEyeball696
Well-Known Member
Still kinda confused on the temperature to run when the lights are off so the dehumidifiers stay on properly. Like I said when the lights go off and temps drop I have my thermostat set to 73, should I go maybe 75 to ensure proper dehumidification? I have whole home dehumidifiers not small single ones. They are set up a little differently 90-95 pints a day X 2 is ample for my 20 x 20. Just kinda confused not on the co2 part cause I have an automatic controller but more on nighttime temps to keep RH 45-50
If I'm in the wrong forum let me know
Thanks
Kush Is My Cologne
organixx325
Active Member
I use humidity controllers to control humidifiers/dehumidifiers. Set it to to whatever humditity you want it to kick on and have it exhaust out when it reaches the set humidity.
Peter Vakomies
Member
Even at night I use 72 deg F, and keep the dehums' going.
I like to keep things cool - The AC's dry the air so well, I like to keep them working hard to increase VPD. Are your dehumidifiers able to keep up ?
CO2 will get into the plant easily if the plant has no water stress, so I keep roots wet and I don't let air get warmer than 78 Deg F.
I'd set the AC's to run at 72 deg F, expecting leaf temps to be 77 deg or so in the day. If your dehum's discharge heat into the grow room, that will also trigger the ACs to run more, and together they'll just wring the water out of the air!
With a big crop I like to see the %RH of the air around 45-50% after irrigating, and I let it go as low as 30-35% before watering, but the soil is always wet. I usually water when the soil has dried to 70% of saturated (measured by the weight of a freshly watered pot= 100%). If roots run out of easy-to-absorb water, growth slows or stops; keep the soil wet !
With dry air and wet roots, plants transpire more, which equals faster and bigger growth. I usually set dehumidifiers to run until 40-45%RH. If you capture the AC and dehum' condensate, it's not unusual to irrigate with 1000 liters one day, and have almost 1000 liters returned to the reservoir within 24-36 hours.
It's true that the enzyme RUBISCO operates faster at warmer temperatures, but letting air temp rise to promote stomatal opening for cooling the plant often increases the air's humidity (lowers VPD). To enable the best use of CO2 we just want to keep the stomata wide open, so avoid any drought or water stress.
In contrast to RUBISCO's preference for warmer temps while it captures CO2 and makes carbohydrates, the photochemistry part of photosynthesis where chlorophyll is catching photons actually runs better at cooler temperatures. The green photosynthetic membranes in chloroplasts will overheat in high light and are constantly trying to dissipate that heat, so I like to keep air temp on the cool side. 70 - 72 deg. F, and keep the CO2 levels between 600 to 1200 ppm.
I like to keep things cool - The AC's dry the air so well, I like to keep them working hard to increase VPD. Are your dehumidifiers able to keep up ?
CO2 will get into the plant easily if the plant has no water stress, so I keep roots wet and I don't let air get warmer than 78 Deg F.
I'd set the AC's to run at 72 deg F, expecting leaf temps to be 77 deg or so in the day. If your dehum's discharge heat into the grow room, that will also trigger the ACs to run more, and together they'll just wring the water out of the air!
With a big crop I like to see the %RH of the air around 45-50% after irrigating, and I let it go as low as 30-35% before watering, but the soil is always wet. I usually water when the soil has dried to 70% of saturated (measured by the weight of a freshly watered pot= 100%). If roots run out of easy-to-absorb water, growth slows or stops; keep the soil wet !
With dry air and wet roots, plants transpire more, which equals faster and bigger growth. I usually set dehumidifiers to run until 40-45%RH. If you capture the AC and dehum' condensate, it's not unusual to irrigate with 1000 liters one day, and have almost 1000 liters returned to the reservoir within 24-36 hours.
It's true that the enzyme RUBISCO operates faster at warmer temperatures, but letting air temp rise to promote stomatal opening for cooling the plant often increases the air's humidity (lowers VPD). To enable the best use of CO2 we just want to keep the stomata wide open, so avoid any drought or water stress.
In contrast to RUBISCO's preference for warmer temps while it captures CO2 and makes carbohydrates, the photochemistry part of photosynthesis where chlorophyll is catching photons actually runs better at cooler temperatures. The green photosynthetic membranes in chloroplasts will overheat in high light and are constantly trying to dissipate that heat, so I like to keep air temp on the cool side. 70 - 72 deg. F, and keep the CO2 levels between 600 to 1200 ppm.
DirtyEyeball696
Well-Known Member
Scottmurphy12
Member
Would you suggest exhausting
What's your thoughts on co2 inhibiting ethylene production late flower, atmospheric levels during ripening phase?
Renfro
Well-Known Member
Well lemme guess, you are using a blower to ventilate your space for cooling purposes? If so, the CO2 is exhausted faster than it's produced.
Terpenefiend
New Member
That high of humidity is causing me anxiety and my monitor and controller won’t even be here until tomorrow. I am now contemplating just send the fuckers back. What’s the point of an increased yield if the chances of losing it to bud rot is that high?
ambiant humidity at 40-50% will reach easily 60-70% humidity when burst of transpiration of the plant occur you both are right but doesn't calculate the same humidity factor ...
TeW33zy
Active Member
WHAT? No no no. The reason you don't run co2 during the last 2 weeks is because of the Ethylene the plant produces to ripen your flowers. Ethylene is a hydrocarbon gas that plants produce at the end of there life cycle to ripen. If you run high levels of co2 while the plant produces Ethylene c2H4 it effects the hydrocarbon compounds. Ethylene has 2 carbon atoms and 4 hydrogen atoms which work together to ripen. This process is undergoing 4 types of reactions - oxidation, polymerization, halogenation, and hydration which is how you buds get that ripen look and oils.The reason for this is limiting factors. Co2/oxygen/light/nutrients/temp must essentially be balanced. If given numbers just for the sake of explaining, let's say you run all factors at '2', but then decide to increase co2 to '3'. To simplify the explanation the plants will still grow at '2' or only slightly faster unless you increase everything. Ed Rosenthal explains it in his book I believe
You never want to affect the Ethylene ripening process, literally 2 gases in high concentrations effect each other. Co2 goes up, Ethylene stays down, Ethylene goes up, Co2 goes down, never ever up at the same time. No different than you guys putting a boveda 62% humidity pack in the jar during the sweating process, u never ever do that. You burp the jar until the jar consistently stays at 56-60% then after its stable a few days later u add the boveda pack so it's not affecting the sweating process. If you run extra co2 while the plant is producing Ethylene c2h4 your plant will literally not ripen correctly and you will have decreased quality, decreased oils, terpenes and everything. Don't do it.
I hope this helps.
~ Sr. Quality Engineer, M.S, (Medical)
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calvin.m16
Well-Known Member
co2 enrichment only needs to be stopped when lights are off. I've noticed no benefit to turning off co2 late bloom.. If your co2 was to shut off the best time would be late bloom though, any other time the plants will be consuming much more of it. When I first flip plants into 12/12 my co2 burner runs a lot more than usual for the first few weeks during stretch, then it kinda slows down and isn't kicking on as much. Late bloom it only runs a few times here n there.. That is how I know at least.. Basic observation over the last couple years of using co2.
p.s don't run co2 higher than 1500 PPM anything higher and your starting to actually cause plants to reduce transpiration and close their stomata due to being enriched with co2 heavily. Keep your co2 ideally in the 1000-1200 range for the best results. I see some new to co2 people running it at insane levels like 2000-2,200, at those levels it can actually have an adverse effect.
p.s don't run co2 higher than 1500 PPM anything higher and your starting to actually cause plants to reduce transpiration and close their stomata due to being enriched with co2 heavily. Keep your co2 ideally in the 1000-1200 range for the best results. I see some new to co2 people running it at insane levels like 2000-2,200, at those levels it can actually have an adverse effect.
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Kassiopeija
Well-Known Member
so when CO2 intake wears down I take it that means the photosynthesis rate slows down, too. which would warrant to reduce light influx, isnt it?
Samwell Seed Well
Well-Known Member
Funny how the plant tells you.. as its finishing its cycle
Eats less, transpires less...
To OP
Plants do all the work, just pay attention and open and close the right doors