HYDRO temperature flowering

[doryan]

Greetings from far over the sea..

..my question is quite simple I guess but I can't find no satisfying answer by myself.

Where 'exactly' do I take the temperature in my growroom??

As I understand nearly perfect would be 26degrees around 80F not higher..

..but at 3 different spots I get 3 different readings..

..on top of the lights around 29 degrees 84,2F..
..right over the plant 31 degrees 87,8F..
..BUT..under the leaves only 23,5 degrees 74,3F

Plant is growing perfect as far as I can see.. no sign of any disturbances. No burns.. no sad leaves.. everything ok.. so my guess is like (31 + 23,5) : 2 =27,25 =81F? As in almost right.. right??

..would really like to know for sure not guess xd

Thank you for your help
..and awesome page thx so much for all that info had great first yields even as a beginner

[bboyfromwayback]

I’ve always kept the temperature/humidity meter right at the top of the plants and it’s worked for me.

[gbauto]

I try to monitor at the canopy.
I also suggest using an instant-read IR temp gun to measure leaf surface temps.

[DW2]

Howdy doryan, I measure the air temperature eight at the level of the canopy. I am using CFLs and keep them very close (3 inches to 4 inches above the canopy). I try to keep the air temperature between 80° F to 85° F. Higher temperatures will stress the plants. The reservoir water temperature is very important as well, maybe more so. I use ice bottles to keep the reservoir temperature between 63° F and 70° F, over 70 degrees and algae can start growing and root rot can start as well.

[doryan]

Mmh..
..water temperature.. sth i didn't thought about yet.. will look for that in the morning.. thx 4 that input..

..sooo.. all of you take temp at the canopy.. on top of it where the lights hit the leaves right?

..so the room temp needs to be way under the 80F to get to the right point.. i wonder how people were able to get there before LED..

Thanks for your time guys ;>

[gbauto]

..on top of the lights around 29 degrees 84,2F..
..right over the plant 31 degrees 87,8F..
..BUT..under the leaves only 23,5 degrees 74,3F

What are you using for lighting???
Based on how much hotter it is at the canopy compared to the fixture, I'm wondering if you are getting a lot of IR radiation from your lamp.
That is why using an instant-read temp gun to measure the leaf surface temp will allow you to dial in the environment using a VPD chart for temp/humidity.

[doryan]

Greenception 700+
..there 4 switches..
1. Growth (some blue between)
2. Full spectrum (and some more red)
3. Full spectrum (and some more blue)
4. Flower (some red between)

..I use 2 and 4 on beliving red is needed for flowering..
I'd put them all on ( what do we need? - more power!!)
..but then it gets too hot


*Google's vpd charts..
..aand a Temp gun.. 20bucks.. so we take two!