Sealed Room Night Temps Question

[Mystre.Pharmer]

Hey everyone. I had a question that I can't really find an answer too. I'm hoping someone might be able to point me in the right direction.

At night time it common to hear "don't let temps drop more than 10F" or stress or stretching or whatever. but my question is, how much of a temp drop is needed? I'm running a sealed room with 2k lights it gets to be ~85-86F during lights on with CO2. Do I have to let the temps drop to 75-76? Currently I get down to 76-77 and maintain but do i need to? am i wasting electricity by unnecessarily cooling the room at night? could i just turn off the lights and let the temps do what they do? it won't get hotter at night than it did during lights on.

Any thoughts would be appreciated.

:banana1sv6:
-Pharmer

 

[Medipatient]

interesting question. I would think that "the rule of thumb" is not to let the temp drop more than 10 degrees of the highest day temp. that doesn't mean immedietly after the lights go out you have to have the A/C turn on and drop it 10 degrees. i think that aslong as within the 12 hour dark pierod it doesn't get hotter and the temp drops by a few then you should be fine.

I could be wrong however. I'd like to hear other peoples thoughts on this topic.

 

[Fred]

CC magazine best of summer 2002 has a great article on this. Basically, if your nightime temps are close to your daytime temps for the first few weeks of flowering you can control the streching phase some. If temps are not brought back down at night to at least 6-7 degrees cooler then the day temp problems will come. Leaf Chlorosis...so i wouldnt do this for more then a couple weeks and in the begining of the 12/12.

 

[DoubleDub]

Interesting theory Fred... Do you have a link to that article?

 

[Mystre.Pharmer]

Hey guys thanks for the replys! I found a link that I think is the article you're referring to. I've got a few questions though.
Why do plants need to have a 6-7 degree difference? whats going on with the plants during that time that makes then require that?
Also, how long should it take to reach that temp difference? like immediately from 85-79F when the lights go off? or more gradual like a degree or two every hours or so.

The real reason behind me wanting to know is because my room uses IceBoxes and so it creates moisture when the room cools. I find that at 79F at Lights out the Humidity is WAY more manageable then at 77F (that I used to drop to at night) was to much to maintain temp and proper humidity. long story short I'm going to grab another dehumidifier tomorrow so I can go back to 77F night temps again and not worry about high humidity. Even during the day my humidity was on the higher part of "ok" so an additional 50pint dehumidifier should fix my issues hopefully. Im still curious about the temps though..

I remember reading somewhere (dont quote me on these numbers) that something like in a 10'x10' sealed room a 1 degree temp difference could mean like 2-3 gallons of water in the air as RH. or something crazy like that, like i said don't quote me ;)


-Pharmer

 

[Mystre.Pharmer]

oops, here's the link:

 

[Fred]

I just said this because when experimenting i found that after a couple weeks of having no temp change i would adjust back to get it cooler at nite again. Ideal difference is said to be 10 but i only get about 6-7 degrees difference and seen no problems. Having said that I now keep it the same difference the whole way through because they dont seem to strech much unless temp diffence is over 10. And it doesnt have to be instant change or anything i would say if the majority of the night is cooler then it will be fine. Glad you found the article. I hope it helped answer the specifics.

 

[kushpheen]

what are the effects of the temperature falling more than 10 degrees at night?

 

[halfdef]

Mystre.Pharmer - many thanks, that is a wonderful article. Answered a question that I had about a plant that wilted and then got burned right under one of my lights. much love.

kushpheen - that link from Mystre.Pharmer answers your question. ;0

one love

 

[Mystre.Pharmer]

glad i could help halfdef. hope others find is useful as well. :) I thought it was a pretty interesting article.

Have a good one!

-Pharmer

 

[halfdef]

Mystre.Pharmer, that is quite the grow in your gallery pics!!

peace

 

[Mystre.Pharmer]

hey thanks halfdef! :) feel free to stop by my current grow journal, the links in my sig.

Happy pharming!
-Pharmer

 

[Jalisco Kid]

If you google greenhouses and DIF you will get more info. JK