Dirtbags Do-over... 🤪 Back to Organic!

[Aqua Man]

You might be on to something with this one Aqua Man. I am running hydro these days and I am noticing some kind of strange things since flipping to flower. First thing I have noticed is an increased in CO2 usage over Coco. Secondly, I am seeing much higher CO2 levels lights out. I usually see something down to maybe 200 at the end of the 12 hours of lights off but I am seeing more like 650 at the same time in hydro.

Yeah in hydro I was seeing well over 2000 ppm at night. Soil not as high.

 

[Anthem]

Yeah in hydro I was seeing well over 2000 ppm at night. Soil not as high.

The growth rates of Hydro over Soil and well old school Coco are insane. They want more food, CO2 and water. Looking forward to how this one finishes off. I have GMO and Ice Cream Cakes running. Cannot believe the smell coming off of these two strains. GMO is one stinky girl so it the ice cream cakes.

 

[beluga]

My knee-jerk surmising...
Fungi/mycelium breathe like us; O2 in, CO2 out.
Correlation?

edit: I should probably elaborate a little more...
I'd assume any soil or even soilless media would have a certain amount of fungal activity... no matter what. And bacterial, and I imagine specific bacteria also respire the same way... is it possible that these living producers are supplying plants via their roots, or even just passively through the soil/less media that's in very close proximity?

 

[Anthem]

My knee-jerk surmising...
Fungi/mycelium breathe like us; O2 in, CO2 out.
Correlation?

Interesting that might help explain the differences I am seeing verses @Aqua Man seeing like 2000 PPM of CO2 at end of lights out because I am pretty sure he runs Micros and I have chosen to run my first couple of hydro runs sterile.

 

[beluga]

Oh, here we go...

Soil Respiration

Just a wiki article, but it covers the gist of what I'm getting at.
Rhizosphere respiration is of specific interest.

 

[Aqua Man]

Rate of respiration by plants and microbes. This happens constantly but for plants more so at night. So the the co2 we see at night is basically from the plants. Number of plants will have a large impact on how it correlates to ppm

 

[beluga]

Rate of respiration by plants and microbes. This happens constantly but for plants more so at night. So the the co2 we see at night is basically from the plants. Number of plants will have a large impact on how it correlates to ppm

Do you know, how do they react/how does CO2 PPM correlate to 24-hour lights on? Do they still cycle at all in a non-light-related circadian rhythm sort of way?

 

[Aqua Man]

Do you know, how do they react/how does CO2 PPM correlate to 24-hour lights on? Do they still cycle at all in a non-light-related circadian rhythm sort of way?

Yes respiration is constant. But during light out respiration rates increase by quite a significant amount. This allows the plant to convert the sugars produced by photosynthesis into we will just call it energy and move it throughout the plant to facilitate growth.

Now depending on light intensity under 24 hrs the plant may or may not be able to keep up. Under low light there is enough respiration and processing of the sugars into energy that the plant may keep up since production is slower.

Under high intensity the plant will not keep up and transition from photosynthesis to photorespiration as it becomes saturated so that it can process the sugars made. This results in a reduced amount of net photosynthesis and growth.

So depending on light intensity you may be able to run 24 hrs but I do not suggest it.

 

[Aqua Man]

With a co2 rich environment the plant can process these more efficiently and thus reducing the risk of photorespiration and allowing a higher intensity of light for a possibly longer duration while still keeping up with processing or atleast improving it so you see a net gain to photosynthesis and growth.

 

[beluga]

you may be able to run 24 hrs but I do not suggest it.

Yeah, me neither. Seems cruel. Cruelty doesn't produce good results (attack me all you want, authentic veal-and-foie-gras-lovers).

But the first part got to what I was curious about - thanks!

 

[tomatoesarecooltoo]

Everything I can find says that respiration rate does not increase significantly at night, and even decreases slightly due to cooler temperatures. Plants release extra co2 at night because they are still respiring, but are not photosynthesizing.

edit: To clarify, this is not in contradiction to the importance of night cycles.

 

[Aqua Man]

Everything I can find says that respiration rate does not increase significantly at night, and even decreases slightly due to cooler temperatures. Plants release extra co2 at night because they are still respiring, but are not photosynthesizing.

edit: To clarify, this is not in contradiction to the importance of night cycles.

Yes you are absolutely right. I should say the balance shifts to far more respiration at night.

 

[beluga]

Is accelerated root production/function also carried out at night?
I'd think the plant would have more resources to do so without all that photosynthesizing going on.
And, it would seem, roots are responsible for nearly half of all soil respiration.

 

[Anthem]

Is accelerated root production/function also carried out at night?
I'd think the plant would have more resources to do so without all that photosynthesizing going on.
And, it would seem, roots are responsible for nearly half of all soil respiration.

I believe most of the plant growth occurs lights out, not just to root system.

 

[beluga]

Really seem ass-backwards that anyone ever thought 24-hour lights-on would somehow produce more.
I mean, I get it.. you get all that stored energy and then flip to flower and WOOSH... batteries in direct connection to bud production. But.. eh. Seems flawed in a functional approach.

edit: Not to offend. I, too, thought 24-hour lights-on would produce more, faster, once upon a time.

 

[Aqua Man]

Good question... im kinda thinking night and first few hrs of lights on.

 

[Aqua Man]

Really seem ass-backwards that anyone ever thought 24-hour lights-on would somehow produce more.
I mean, I get it.. you get all that stored energy and then flip to flower and WOOSH... batteries in direct connection to bud production. But.. eh. Seems flawed in a functional approach.

edit: Not to offend. I, too, thought 24-hour lights-on would produce more, faster, once upon a time.

It's really going to depend on light intensity. Under low light its a benefit IMO. But I would never grow under low light because the bud production would be crap under 12/12. But an auto... its a good option if you have limited light.

Its really going to boil down to DLI. Hell you can veg under 16/8 or 24/0 and have similar growth... maybe not structure wise but in terms of mass. If the intensity of the 16/8 is 1/3 higher then growth should be similar in mass.

 

[Anthem]

It's really going to depend on light intensity. Under low light its a benefit IMO. But I would never grow under low light because the bud production would be crap under 12/12. But an auto... its a good option if you have limited light.

Its really going to boil down to DLI. Hell you can veg under 16/8 or 24/0 and have similar growth... maybe not structure wise but in terms of mass. If the intensity of the 16/8 is 1/3 higher then growth should be similar in mass.

It comes down to the Mols per day. I cannot remember off the top of my head but Bruce B. mentions it in one of his You Tube Video's

 

[BudGoodman]

I caused a little controversy... Sweet!
I've been veging on a 24hr cycle for so long, I forgot it was even odd.
Just for reference, those plants pictured earlier were worked up to 54 watts per square foot of t5 (bulbs 50/50) before being moved under 75wps of HID (currently MH) to flower... All open atmosphere.
24 hour veg, a day flower and a night flower... Dial those three rooms in to work symbioticly (?) within a lung.
Make sense?

 

[Aqua Man]

It comes down to the Mols per day. I cannot remember off the top of my head but Bruce B. mentions it in one of his You Tube Video's

Around 60 DLI at atmospheric co2. Would be around 925ppfd over an 18hr period