Philips 3k Vs Philips 4k Cmh In Flower

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This is a test of the Philips 3k and 4k cmh bulbs in flower. I'll need your input as well comparing pics. I should be able to match week for week. All done with same strains, same room placement, same temps/rh. I will need to lower co2 from 1200 back to 1000. Lessen the variables.

Bulbs being tested

Philips master Greenpower elite agro t12 930 (3k)
Philips master color cdm elite t9
940 (4k)

1 brand new bulb far left (#1) hood. All other bulbs have maybe 1200hrs tops. Fixed hoods, I use cinder blocks, milk crates, or tubs to raise plants between 36-48" tops.

1 thing I did notice, (may be due to the winter weather, cold basement) my a.c. doesn't need to run as often as my co2 is lasting much longer. I'm betting the 4k isn't as hot as the 3k bulb.

Here's a link to a past cmh grow.but with the 930 (3k) flower bulb.
https://www.thcfarmer.com/community/threads/demons-4x315cmh-v2-0.86733/
I'l try and get some pics later.

Flipped 11/2 to 12/12
I'l take these to 64+ days. I tossed in a cannatonic4 cbd last night. My patients will be needing her soon.
 
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So from my understanding you can use both 3k and 4K for flower or veg?is it jus the light cycle that determines flowering?

You can run any kelvin/spectrum.bulb you like at any time from.seed to chop. Choosing the proper spectrum for said plant type is key.




Today is 12 days from flip. I hope it' not the "placebo effect" (could very well.be), but I'm noticing a difference already.
1 less stretch with 4k
2 tighter nodes with 4k
3 quicker developed bud sites. I don't remember them.being this nice this early.

Tomorrow the last of the tubs get removed, and either 1 or 2 nets are going up and weaving the taller tops to match the little shorter ones.
 
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15 days from flip

Few pics from tonight
Controller set to 84*, 1000ppm co2
Rh avg 65-70% lights out, 65% lights on.
Need to set up my deheuy in 3 weeks. I don' really worry about rh or lowering temps until the buds start to fill out (week 5ish). Net went up tonight. I'l
Tuck a few tall ones and hope to even it out a bit more.

I still believe the 4k lights run cooler (less a.c. usage), less stretch, and closer nodes than the 3k. As far as yields, still 8 weeks away, then cure, so about 11 weeks.


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Been swamped lately. Pics are 2 days ago. 20 days from flip. I need to tuck some of the super tall ones a bit down to try and even out the canopy. It' still better and easier than stakes. Every 4th day it's the usual feed or water/silica time. Same as always with the 930 bulb.

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I'l snap a pic of what happens 1 week before you flip when you top. Makes that particular top bud/grow funny. Looks liken it was grown near Chernobyl .
Lol
 
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