C02 in the Dark

My temps during lights on keep me from being able to turn off any fans, so I've stopped supplementing C02. Would the plants get any benefit from C02 dosing during the dark period? Maybe hit them minutes before lights on?

Right at lights on, with no fan would work. Plants don't process CO2 from my understanding unless they are photosynthesizing. Maybe getting a cool tube for your light would help. That way all the majority of the heat is taken out of the grow room.

Plants have stored energy during the day. They use lots of this at night for roots. And lots is wasted because it's there for emergencies to keep itself alive during stresses. You can take advantage of that. Half hour before lights out, go and blast co2 from the tank till your at about 3000 ppm. Make sure plants are fully watered before doing this. Fans off. Co2 lowers temps at first. After lights off half hour vent room and reset your normal night fans. Best if done every other night. Plants will grow over night. Not so affective on buds. Makes them weird looking. They need co2 consistent.
Also, Never add co2 after lights out. It will kill your plant.

Cannasutraorganics said:

Plants have stored energy during the day. They use lots of this at night for roots. And lots is wasted because it's there for emergencies to keep itself alive during stresses. You can take advantage of that. Half hour before lights out, go and blast co2 from the tank till your at about 3000 ppm. Make sure plants are fully watered before doing this. Fans off. Co2 lowers temps at first. After lights off half hour vent room and reset your normal night fans. Best if done every other night. Plants will grow over night. Not so affective on buds. Makes them weird looking. They need co2 consistent.
Also, Never add co2 after lights out. It will kill your plant.

Click to expand...

What? Co2 will kill your plants in the dark?! Huh?
But you just said they need CO2 consistently?
Please elaborate, as this is completely not what I've ever learned or read. Why would you blast them with CO2 with only 30 mins left on the light cycle? And fully watering them right before a night cycle isn't the wisest either. I'm not trying to be an internet-dick, but this is contrary to what I've learned. I'll gladly admit it, if i'm wrong

vostok said:

The number one reason pro growers use C02 in the their grow room, is that the plants can continue to grow even at high temperatures, above the rec. 25c/77f...up to and beyond 35c/95F and more sativa in the mix the better and even more tolerable of heat, tho Rh is vital ...watch your temps and Rh, some buddies even have sensitive atmosperic pressure gauges to monitor the increase in room pressure ...lol

Click to expand...

I always liked using CO2 with my metal halides for the vege time, it worked amazingly good on getting the plant's stems much thicker, (especially varieties that like to stretch when triggered.....sativas) and able to withstand the heavy nugs later in life. Most people I knew liked it for the flower times, but I had better results with more airflow for flowering, at the time it was a small grow room for the flowering so it had problems with heat, when I enrichened the room with the exhaust fan off. Worked damn good for the vege room though, in the end I stopped using it. I actually just gave my tank and regulator to my buddy, it was simply taking up room.
Honestly, I used CO2 for about four or five years, with about 5-6 runs a yr, in the end I didn't notice much of a difference, but no question it made them MUCH stouter when veged, not to mention they simply grew faster. My flowering room had too many lights for CO2, it's kind of a catch 22, if you REALLY want to see the true benefits of CO2 you need a lot of light, but conversely a lot of light needs a lot of ventilation....
ohhh man, i'd LOVE to have a sealed greenhouse, in a cool area, and then you could truly see what CO2 can do... can you imagine what the sun AND enriched plants would do? You could probably pull up a chair and watch them grow, like bull-kelp.

Cannasutraorganics said:

Plants have stored energy during the day. They use lots of this at night for roots. And lots is wasted because it's there for emergencies to keep itself alive during stresses. You can take advantage of that. Half hour before lights out, go and blast co2 from the tank till your at about 3000 ppm. Make sure plants are fully watered before doing this. Fans off. Co2 lowers temps at first. After lights off half hour vent room and reset your normal night fans. Best if done every other night. Plants will grow over night. Not so affective on buds. Makes them weird looking. They need co2 consistent.
Also, Never add co2 after lights out. It will kill your plant.

Click to expand...

its very simple when mj is awake it takes in co2 and puts out o2. When they sleep its the opposite. While they sleep they take in o2 and put co2.

hyroot said:

its very simple when mj is awake it takes in co2 and puts out o2. When they sleep its the opposite. While they sleep they take in o2 and put co2.

Click to expand...

nah man, it's obvious that co2 kills plants.... Im kidding

Luckily, my Rh is golden; it's pretty arid where I'm at. I agree with C02 in veg...strong, lush healthy growth. I like to use it in flower too though, I do think it helps with weight.
Thanks everyone for the replies.