Separate flowering room for 12 hour dark cycle with no ventilation or fan

I’m flipping 1/2 of my plants to 12/12 for flowering. i plan to move them in/out of my 18/6 (1000w LED) room to a dark box every 12 hours, but the dark box has no ventilation or fan. humidity is about 40% and temperature is consistently 70-75 degrees in both environments. will this be a problem? btw, the fan in the 18/6 room is on/off on the same schedule as the lights and the plants don’t seem to mind 6 hours of no fan.


If it’s working for you that’s great.
My thoughts are I want to keep exchanging old air with fresh are 24/7 using an inline fan as well as small fans in space for air movement.
As long as your able to keep temps and humidity within range keep doing what works for you.

Here is a chart showing temps/humidity relationships for optimum growth.

Hope this helps


@Skydiver Hey thanks for posting the chart. That just helped me a heap :slight_smile:.

Are these temp and humidity readings with the plants in the box…?
Humidity always rises during the dark period…
Because that’s when the plants will use the energy that they have stored during the light hours which leads to heavy transpiration… :wink:
I would figure out a way to hook up a cheap extraction fan… :+1::wink:
Pulling plants in and out is going to get old quick… :+1::wink:
Hopefully you can keep up… :+1::wink:

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thanks @peachfuzz and @skydiver

the ventilation is key and i’ve updated my timer turn the intake/exhaust on a few times during the dark 12. and you were right, moving the them got old and the plants are getting too big to be constantly moving. i’ve put my plants in veg outdoors with some supplemental t8s (hopefully better than nothing) in the evening to get 18 hours.