Is it ok to run fans the entire 18 hour light cycle?

My plants are in week one and two. My tent exceeds 85 degrees F if the fans are not running. With the fans running it's anywhere from 77 degrees to 83 degrees F. I don't have my fans blowing directly on the plants. My question is: the only time my plants will be able to absorb CO2 is during the dark; is this enough? or should I consider using a CO2 tank?

Stop everything you are thinking.

Plants take CO2 during lights on ONLY. If this is your first grow, don't bother with CO2. You're taking on too much.

Assuming you forget CO2 for now, you need to vent your air all day and night, cycling the full volume every 5-10 minutes. That's your exhaust fan. Mine is always on. Others may differ, but the bottom line is you need to cycle your air often, bringing in new CO2, and reducing heat.

There can/should be another fan blowing air over your canopy. This can be turned off at night, though mine always stay on.

What's your setup? Before you go buying CO2 equipment.

If you are a newb, and there's nothing wrong with that, I am too, but don't go trying to grow a pound your first grow. Don't TRY to maximize yield. Just try to grow a plant.

Please trust me. I want you to harvest homegrown gold.

Seal up the room and throw an a/c + humidifier to use c02. Otherwise dont waste your time and money.

Trim is correct. Its the photosynthesis process that needs c02. You also need enough light to make use of it.

I love how the ego gets gently checked on here!

Also if you don't run your exhaust fan during lights off. You're most likely going to have a problem with the humidity spiking. Not good during flower...

mean.green said:

My plants are in week one and two. My tent exceeds 85 degrees F if the fans are not running. With the fans running it's anywhere from 77 degrees to 83 degrees F. I don't have my fans blowing directly on the plants. My question is: the only time my plants will be able to absorb CO2 is during the dark; is this enough? or should I consider using a CO2 tank?

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I was having an issue with high temps in my tent, simple solution, open the top flap and keep the bottom open, that will allow the warm air to rise out while drawing in fresh air from below. I keep the closet door open during the day while the lights are off, after the lights go out, I close the door to keep unwanted light out. Never used Co2 in my grows. Just seems like overkill for such a small space

3x3x5 tent, Two 200w cfl for flower (total 400w), two 125w for veg (total 250w), 5 plants, planning on doing scrog, two 6 inch fans (one to send air out and one to circulate the tent), one big fan placed at the bottom to send 72 degree F air in the bottom.

I run all 3 fans to keep the temp between 77 and 83 degrees.

I know HID or LED or MH is better than CFL but I want to start small/ cheap to learn. However the CFL's heat the tent fast.

I was just making sure having the fans on during the entire light cycle would not result in slower growth. But I don't really have an option now because I've already started with the setup I described.

Temperatures during dark cycle are about 66 degrees. I exhaust stale air halfway between the dark cycle for 20 mins.

My plants are only a few inches high at about 2 weeks old with 3 nodes maximum.

You can run all fans 24/7 with no worries. Have a fan blow on your plant or if at least not directly on it(if you feel its too strong of wind) against a close wall that reflects the wind onto the plant to keep the plant in a breeze. That breeze will strengthen your stems/branches.

As mentioned don't worry about CO2 right now.

Anon Emaus said:

You can run all fans 24/7 with no worries. Have a fan blow on your plant or if at least not directly on it(if you feel its too strong of wind) against a close wall that reflects the wind onto the plant to keep the plant in a breeze. That breeze will strengthen your stems/branches.

As mentioned don't worry about CO2 right now.

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Yea what he said about the fans, you want to see a little movement on the stems/branches/leafs but not so much it's flapping around. It will help them grow stronger to support larger buds.

Anon Emaus said:

You can run all fans 24/7 with no worries. Have a fan blow on your plant or if at least not directly on it(if you feel its too strong of wind) against a close wall that reflects the wind onto the plant to keep the plant in a breeze. That breeze will strengthen your stems/branches.

As mentioned don't worry about CO2 right now.

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Thank you Anon and dgthumb for the re-assurance! Also thanks Russ668, TrimothyLeary, dgthumb, and SPLFreak808 for the responses!!!!!

mean.green said:

Thank you Anon and dgthumb for the re-assurance! Also thanks Russ668, TrimothyLeary, dgthumb, and SPLFreak808 for the responses!!!!!

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Welcome and best of luck!

mean.green said:

Thank you Anon and dgthumb for the re-assurance! Also thanks Russ668, TrimothyLeary, dgthumb, and SPLFreak808 for the responses!!!!!

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Hey, no problem. Good growing!

mean.green said:

Thank you Anon and dgthumb for the re-assurance! Also thanks Russ668, TrimothyLeary, dgthumb, and SPLFreak808 for the responses!!!!!

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You're most welcome. This site is fabulous for brainstorming and contributing, think all of us in a way want to see each other produce bad ass grows. Hooray for group efforts!

everyones said it already; your plants want fresh air, just like you and i do. i keep my ventilation running 24/7, cool air coming in, hot air going out (preferably to a window or another source of fresh cool air. Remember heat rises, so i put my exhaust vent at the roof of my tent, and pump in cooler air through the middle and bottom vents of the tent. this isnt even including the oscillating fan(s) i got on aimed at the plants. I agree though, just try and grow your first plant before tackling things like CO2 . It starts as an experiment and then a hobby, and then your religion lol, happy growing!