Whats up with 24/0 light schedule?

be4meliz

Well-Known Member
Probably start a S**TStorm, understand the need for more light time with artificial(based on lumens produced) but in my minor in Botany, we studied Photosynthesis and basically all plants need a dark period to complete the process. My Autos are on 18/6 and are doing GREAT! Just wondering how this evolved.Not to argue, just tossing it out- Have seen 18/6, 20/4 and 24/0- Just feel they need a certain amount of sleep.Not to mention saving on the light bill, especially with Hid
 

be4meliz

Well-Known Member

be4meliz

Well-Known Member
Agreed, Poontanger, I have a cold basement,avg.@ 40 deg, ,so with Led very little heat, so incorperated small ceramic spaceheater, with adjustable therm. to keep temps@ 75-80,vent fan set for 10 min. every 2 hrs( except dark hours)iwith passive intake(humidity)

Just test drove my Big tent tonight and will definatly need exhaust with it. Running 2 M/h 600 watt,(with 3 planned} temp went up to 88 degrees over 1 1/2 hrs and Rh from 39 to 21.- no setup -just bare tent and lights( gonna be an 8 pot DWC) So 6/2 might work to keep temps down,
once I figure plumbing. This tent is 4 by 8 by 6 1/2' tall.Have 3 600 watt total M/h- Hps. I want to plumb all 8 together into a recirculating system with a large res. as keeping up with individual pots for nutes ,ph, ppm will be rediculous .Any help on that would be greatly appreciated: parts ,fittings,schematics, etc.

Moses- 24/0 showed that plants stressed and created Herms. Thats what they do for survival
 
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ttystikk

Well-Known Member
Hey a 6-2 light scheldule works well to , helps in temp drops @ night
I run 24/0 in my babies room and 6/2 in prebloom veg. Everyone sure seems happy...

I'm gonna try the 6/2 for the wee ones and see what happens.

I feel it's important to note that I run very strong light in my veg, basically bloom strength. I don't believe in growing plants in the dark and besides, springtime never seemed dimmer to me than summer.
 

be4meliz

Well-Known Member
Hi, ttystikk,
Like I mention on posting- this is all up for discussion- that's what i want to hear, from experienced growers- the pro's and cons, what works,etc. -they are after all Weeds, but trying to gain the best approach for the best quality and highest yield, and proper lighting is the # 1 priority, be it Cfl, Led, or Hid and all in the proper amounts- can't match the sun's intensity, but we can get damn close.
We are all mad scientist- and all chasing the ultimate at all levels (micro> max).
By the way, love your nametag, as I have very fond memories of Colorado and Thai stick in 1975.Peace
 

heckler73

Well-Known Member
The Calvin cycle or Calvin-Benson cycle will explain it further
https://www.reference.com/science/needed-photosynthesis-occur-40fabd1a3bbbec76#
Converts CO2 > sugar( simple Story)
Another more detailed
https://www.wyzant.com/resources/lessons/science/biology/photosynthesis/light-dark-reactions
Understandably, we can't match Mother Nature in lighting, but we can come close, based on types used. But even in Nature,we have nightime. We just have to compensate for weaker light 18/6, 12/4,etc.
I thought Govindjee did a good job explaining it.

fig04-Gov-Z.jpg

Now, I'm not sure where the "darkness" fits in with all that excitation by EM radiation. Are you talking about the difference between C3 and C4 plants? You might be taking the term "dark reactions" too literally. They are "light independent", meaning they don't need light to finish their work.
 

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OldMedUser

Well-Known Member
Agreed, Poontanger, I have a cold basement,avg.@ 40 deg, ,so with Led very little heat, so incorperated small ceramic spaceheater, with adjustable therm. to keep temps@ 75-80,vent fan set for 10 min. every 2 hrs( except dark hours)iwith passive intake(humidity)

Just test drove my Big tent tonight and will definatly need exhaust with it. Running 2 M/h 600 watt,(with 3 planned} temp went up to 88 degrees over 1 1/2 hrs and Rh from 39 to 21.- no setup -just bare tent and lights( gonna be an 8 pot DWC) So 6/2 might work to keep temps down,
once I figure plumbing. This tent is 4 by 8 by 6 1/2' tall.Have 3 600 watt total M/h- Hps. I want to plumb all 8 together into a recirculating system with a large res. as keeping up with individual pots for nutes ,ph, ppm will be rediculous .Any help on that would be greatly appreciated: parts ,fittings,schematics, etc.

Moses- 24/0 showed that plants stressed and created Herms. Thats what they do for survival
You should have a temp/RH controller for your exhaust fan so it comes on when needed and not on some set schedule that likely isn't the best for your plants. I've been using one for a dozen years and recently bought the parts to make another one. With a baseboard thermostat on my heater my room temps are always in whatever range I set the controls to.

Made a speed controller from a ceiling fan control too so the fan only runs half speed when it turns on.

FanControl.jpg

:peace:
 

be4meliz

Well-Known Member
OldMed- appreciate the feedback- can't afford at the moment, so i'm experimenting with my fan controller and no timer, set at low speed running 24/7, will report back- fighting keeping the heat up to high 70's with heater while dropping Rh to nominal percentage. so far, higher RH is not an issue but with flowering will be and these are Autos so need to find a middle ground soon.
 

OldMedUser

Well-Known Member
High RH doesn't really become an issue until the colas are getting really big and moisture builds up inside them. If it's still a problem later make sure you have a strong oscillating fan pushing the tops around a bit to keep moving the air well. Bud rot usually starts in the middle of the colas and you often don't know it's going until a cola falls apart or you see a brown area on the side as it starts busting out. If that should happen turn the fans off first then put a bag over that cola and seal it around the stem before cutting it off the plant. If you mess with it first you'll release spoors all over the place and it can all go to shit.

I forgot to mention about the light period issue. With autos running them at 24/0 until they start flowering will retard flowering for a week or more so they can get larger before setting bud. Then I'd go with 18/6. With photo plants grown from seed it can produce more males so The Rev says to use 16/8 light when starting regs from seed but with clones it doesn't matter as their sex is already set.

I like 24/0 for revegging plants and as they don't need a lot of light until they start growing new, single-bladed leaves a couple of CFLs are cheap to run steady. I've revegged by having them off to the side of vegging plants in lower light going 18/6 and that works too but seems to take a week or more longer. Years ago I lost a couple great strains as I didn't take clones and didn't know about revegging. Not all plants will reveg but it's worth a try if you find out a plant is the shit and didn't take cuts.

:peace:
 

be4meliz

Well-Known Member
After an hour of running exhaust steady on low speed ,Rh hit 50-temp at 72, so turned heater up a notch-target 78-80 with RH 50.
 

OldMedUser

Well-Known Member
So you can get an extra week+ of veg time from an auto by keeping the lights on 24/0? I never knew that or heard of it that is really good to know... Have you personally done that yourself?
Yes I have but as it was just a first run I'm not sure what the effect was. I'll be doing more autos with the strain I'm breeding so there's more experimentation in the works. I've read that about them in many Auto threads along with starting them in the biggest pots that you plan to use for the biggest plants. Seems they perform better if they don't go thru repotting like I do with photoperiod plants.

I've mostly just grown autos to get more seeds and haven't really tried to grow them for size. They stay tiny in small pots and that I know for sure. :)

:peace:
 

OldMedUser

Well-Known Member
After an hour of running exhaust steady on low speed ,Rh hit 50-temp at 72, so turned heater up a notch-target 78-80 with RH 50.
I like 75 for growing. Letting my night-time temps get down to 60 now to try and bring up the purple in my plants. Was running up to 90 when they were in stretch and I was pumping in CO2. They liked that but my tank ran dry.

:peace:
 

be4meliz

Well-Known Member
I'm with ya, OLDMED- with my led setup,hi temps were no issue -had to get small ceramic space heater to raise(45 deg. basement) added exhaust fan to drop Rh (was hitting 80 per.) using speed control and passive intake, now avg. 76 deg. and 50 % RH. .Takes a bit to dial in. Rh rise was due to Drip/DWC system
 

OldMedUser

Well-Known Member
Gotta remember RH goes up a lot as the temps go down after light's out so if you have an RH switch then the fan will come on just long enough to bring the RH down. You could make one of those with a bathroom fan switch cheap enough. That's all that's in my controller. The thermostat for the heat control is a cooling thermostat like you would use for an A/C unit. Works backwards compared to the one that runs your furnace.

Here's a wiring diagram for that unit of mine should you need it.

humidist.gif

:peace:
 
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