Currently 5 weeks into the grow using a 18/6 lighting schedule. While the lights are on my humidy pegs at 50%, when the lights go off it shoots over 60% - 5x5 tent with a 6in exhaust fan - would it be benifical to go to a 24hr light schedule to control humidy and provide extra light durning flower? Or am I over thinking things?
Most growers run autos at 18/6; however, cannabis is a C3 plant that does not require a dark period to complete all biological processes to be healthy. Run it 24/0 if you wish. You will find growers who insist that weed needs a dark period for “sleep” to be healthy. This is not true.
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Im one of those guys 
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Imo. That would a bigger mistake then growing autos. It would mainly just drastically increase you electricity bill. And if its not growing fast enough or how you wanted, maybe its the gentics. And did you mention your lighting?
What does C3 mean sir?
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I’m surprised that the humidity goes down with the temperature. Its normally the hotter the air the more water vapor it will hold.
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Every article, post, etc I read the higher electric bill is the first thing mentioned. I’m running LEDs, bumping it up a 24hr schedule may cost me another $3/mth
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Okay. @BudZ47 try it. I still dont know what a c3 plant is ,but weed will grow just fine under constant light. when i am veging i run my light with no timer(24 hrs.) Some autos respond better to less light bc the photo genes are dominant.
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Some growers swear by a 24-hour light cycle for their autoflowering plants. This is simply because cannabis is a C3 plant, it can absorb CO2 during periods of light for photosynthesis.
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Me too brother
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Some use a 20/4 light schedule
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I AM a noob, but I like to give the plant 6 hours to rest. It doesn’t necessarily need to, but I like to think it gives the plant time to focus on healing itself and settle its roots. You’re free to do as you wish, and if you know what you’re doing with your other grow aspects then 24/7 won’t hurt.
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That’s the problem, I don’t know ish - first grow. Wondering if the higher humidity is more detrimental to my plants vs a 24hr light schedule
Higher humidity is definitely more detrimental, and harder to battle without an expensive dehumidifier. Humidity during flowering needs to be low, around 40% if not lower. In your case I definitely recommend it. I also recommend saving for that controllable dehumidifier for when the time comes, I haven’t done it yet but I’m currently in the process and it will make things so much more easier. I’m battling high humidity, I’m two months into veg and my humidity is up to 60% with lights on so I have to constantly blast air through to prevent mold
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Are you on municipal electric or so you have small fixtures im on municipal running 2 scorpion diablos and my electric bill is over 100 dollars lmao
I have run 24 hour schedule since starting, going on week 5 in 2 days. The largest is showing signs of flowering starting, 2 smaller maybe. Just switched to 18 hour cycle and got utility bill $20 more than previous month but ac running all the time, so really dont see much change. Its hot here in the big easy!
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I just bought a house in a town with no municipal im dreading the bill lmao
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Utilities here were a shocker after years of cheap TVA rates.
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It’s how they process/absorb CO2, lots of geeky science if you really want to dig into it, with a Google search…
The short of it (dumbed down) C3 plants are able to absorb CO2 in sufficient quantity under light in real time to continue their photosynthesis process at full speed… On the other hand, C4 plants use the dark periods to absorb extra CO2, when the light comes on they tap into this nighttime reserve so they can photosynthesize at full speed as they are unable to absorb quickly enough in real-time and thus once that overnight reserve is empty their photosynthesis process slows down drastically… Basically, C4 plants need downtime to absorb enough CO2 to optimize photosynthesis when the lights come on, while C3 plants are able to absorb CO2 fast enough in real time that they don’t need a dark period to recharge…
That said, there is always the trade-off to cost vs net return, 24 hours of light in theory will net the most return, but it might not be the optimal return for money spent…
For example (made up) a 24 hour light cycle may net 100 oz of product, but you might find that an 18 hour light cycle nets 90 oz of product… So for 25% more electricity, you are only netting 10% more product aka less return on investment… Of course, this is all theoretical, so many other variables to consider…
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