Question about best temps to veg vigorously?

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Smokenpassout

Well-Known Member
My temp is a steady 80 and humidity 65. I’m using an AC Infinity thermoforge for the first time to get to 80, as I usually would just be ambient room temp of 72ish. Then the temp would drop a bit at night as well. The thermoforge heater regulates this temp 24/7. Should I set it to power down during my 6 hour night cycle? Thus lowering temp at night to ambient temp, then ramp back up to 80 during the 18 hours of day light? They have been running the same temp day and night and look very healthy. Thanks.
 
I use a Thermoforge, as well, and I set it to maintain 76° during lights out. That was based on the advice from Bugbee in the video below.


For info on growing, in general, the video below is time well spent.

 
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Please share the process of setting thermoforge to do that. Mine is currently set on Auto with the low temperature trigger to 80. So it keeps the environment 80 twenty four hours a day. Also how do you have your intake fan set? Mine is currently set to On and at 7. I did this to keep fresh air coming in 24/7 and scrubbed outake always exhausting. However maybe I should set it to Auto with a temperature trigger?
 
Smokenpassout said:
Please share the process of setting thermoforge to do that. Mine is currently set on Auto with the low temperature trigger to 80. So it keeps the environment 80 twenty four hours a day.
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I wish I could walk you through it but my tent is down for the summer. Best advice I can give is to call AC Infinity tech support and get them to walk you through it.

Smokenpassout said:
Also how do you have your intake fan set? Mine is currently set to On and at 7. I did this to keep fresh air coming in 24/7 and scrubbed outake always exhausting. However maybe I should set it to Auto with a temperature trigger?
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I'm in a 2' x 4' tent so I just use their 4" inline fan. Running it at 4/10 gives me good air exchange (the air in the tent is exchanged once every minute).

Temperature control is important but you should also have air exchange to ensure a fresh supply of CO2 and to control RH.

What size tent and fan are you using? I got ragged on by a grower (different site and he was a bit of a tosser) so I did some research about air exchange and, as expected, opinions vary. The attached PDF shows the data for a 2' x 4' x 8' and uses the CFM rating of the AC Infinity 4".
 

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Delps8 said:
I wish I could walk you through it but my tent is down for the summer. Best advice I can give is to call AC Infinity tech support and get them to walk you through it.


I'm in a 2' x 4' tent so I just use their 4" inline fan. Running it at 4/10 gives me good air exchange (the air in the tent is exchanged once every minute).

Temperature control is important but you should also have air exchange to ensure a fresh supply of CO2 and to control RH.

What size tent and fan are you using? I got ragged on by a grower (different site and he was a bit of a tosser) so I did some research about air exchange and, as expected, opinions vary. The attached PDF shows the data for a 2' x 4' x 8' and uses the CFM rating of the AC Infinity 4".
Click to expand...
Tent is 3X3 AcInfinity. Fan is a 4”. I know that is the bare minimum size for a 3X3 and a 6” is more capable in that space. For now I don’t want to ante up for a bigger fan/filter. Otherwise my light is an EVO4 and I have two oscillating fans (one on the light ballast up high, one moving plants down low. I will take your advice and give them a call thanks.
 
Smokenpassout said:
Tent is 3X3 AcInfinity. Fan is a 4”. I know that is the bare minimum size for a 3X3 and a 6” is more capable in that space. For now I don’t want to ante up for a bigger fan/filter. Otherwise my light is an EVO4 and I have two oscillating fans (one on the light ballast up high, one moving plants down low. I will take your advice and give them a call thanks.
Click to expand...

Screenshot of your tent volume and the capacity of the 4" fan.

Your tent is 54 cubic feet and the fan will move 165 cubic feet per minute.

On a setting of 4/10, the fan will move 66 cubic feet so you'll be replacing the air in the tent in just under 60 seconds.

If you want to change the air every 3 minutes, that's 0.33 changes per minute (I'm using "∆" to indicate "change").

With a big tent, at least 4x4, I can see having a fan to draw air in but, if you've got an exhaust, it's got to draw air in or else the walls would collapse.
I think you're in good shape.



1749170455993.png
 
Warmer temps = more growth there's a relation there for sure up to a point, Imo you'll see quite a difference from your ambient 72⁰f

For 24hrs heat idk, logic would say to me warmer temps should help but idk for sure, the rational side of me thinks a constant 28⁰c might be a bit much, it's worth considering those temps 24hrs will affect your ec and if you've fans blowing directly into your plants you'll need to make allowances for it.
 
Don't blow wind directley on plants
At 24 hour light, at 31c with 80RH, your plants are in turbo mode, every 1-2 hours youll open the tent and wont believe the rate of growing
Those are optimal conditions, at those conditions its imperative to maintain correct feeding and watering.
 
PTS.Genetics said:
Don't blow wind directley on plants
At 24 hour light, at 31c with 80RH, your plants are in turbo mode, every 1-2 hours youll open the tent and wont believe the rate of growing
Those are optimal conditions, at those conditions its imperative to maintain correct feeding and watering.
Click to expand...


At 31°C and 80%RH, VPD is 0.6. That temperature is high enough that photosynthesis is starting to drop (per the graphic from Chandra) and that VPD is so low that water uptake, which is responsible for ~90% of the amount of nutrients that are taken up, will plummet.

If the plant is subjected to that temporarily, growth will stall there won't be long term damage. A grower could compensate lack of nutrient uptake for that VPD by running very high EC but there's still the issue of unusually high temps.

At 80°F (27°C) and 65%RH, the grow is optimal (RH is not going to be accurate to more than a few %) and the temperature it going to result in a good rate of photosynthesis.
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Smokenpassout said:
My temp is a steady 80 and humidity 65. I’m using an AC Infinity thermoforge for the first time to get to 80, as I usually would just be ambient room temp of 72ish. Then the temp would drop a bit at night as well. The thermoforge heater regulates this temp 24/7. Should I set it to power down during my 6 hour night cycle? Thus lowering temp at night to ambient temp, then ramp back up to 80 during the 18 hours of day light? They have been running the same temp day and night and look very healthy. Thanks.
Click to expand...
These autos have been getting 26 degrees and 60-65 rh lights on and down to 18 to 20 degrees lights out and are loving it. If things are going well for you don't change anything
 

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Delps8 said:
At 31°C and 80%RH, VPD is 0.6. That temperature is high enough that photosynthesis is starting to drop (per the graphic from Chandra) and that VPD is so low that water uptake, which is responsible for ~90% of the amount of nutrients that are taken up, will plummet.
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Stop looking at charts, this is bro science
27c and 65 rh you are not even starting to scrape the optimal growing conditions you can apply at indoor growing.
Stop looking at VPD
Plants thrive in high heat high humidity regions, just look at Jamaica or the Amazon
Chandras chart is nice, but false.
Same as claims of 800-1000 ppfd at flower max, etc etc, the bogus claims dont stop.
Water uptake and nutrition is at optimal range in 30c + temps and high humidity 80RH at least.
Delps8 said:
If the plant is subjected to that temporarily, growth will stall there won't be long term damage. A grower could compensate lack of nutrient uptake for that VPD by running very high EC but there's still the issue of unusually high temps.
Click to expand...
No, growth will not stall, the opposite will happen, growth will explode.
Delps8 said:
At 80°F (27°C) and 65%RH, the grow is optimal (RH is not going to be accurate to more than a few %) and the temperature it going to result in a good rate of photosynthesis.
View attachment 5468293

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Again this is bro science, this is a good rate, not optimal in no way shape or form.
 
The very optimal temps and RH if the grower can maintain it 24/7 is 32c ambient and 80-90RH
At those conditions, you push photosynthesis to its max capabilities.
27c and 65 RH is good, not optimal.
What you'll grow in 3 weeks with 27c, i will grow the same size in 2 weeks under 31-32c with added RH.
 
Everything is smooth sailing when your in the 26-28c with normal RH
But its not optimal
When time is a factor, you wanna run everything to the max
But its also risky fosure if your not on it 24/7
Grow on buddies
 
I think it was Migro but maybe Dr. Bugbee who said 84f was the ideal temp. With CO2 bags and a timed water pump drip watering a little 8x a day every 3 hours I've been getting monster buds recently. My tent tends to naturally sit around 84f in winter in summer its closer to 86f.

Oh lol I went looking and apparently the newer science is "it depends".
 
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