ThanksRandomblame wrote: ↑Sun Jul 07, 2019 5:29 am3-5° less leaf temps is a bit much IMO. LST should actually stabilize 1-2° lower than ambient. At the end of the day my leaf temps are often as high as my ambient temps or within 0,5°. Only the 1st half of the day LST stay slightly lower but -2° they reach within the 1st hour.Or_Gro wrote: ↑Sat Jul 06, 2019 9:12 pmThe chart rb showed clearly shows higher lst,, upto a point, increases productivity.TEKNIK wrote: ↑Sat Jul 06, 2019 8:44 pmFrom my limited understanding of co2 intake and maximum micromouls it is in direct relation to the spectrum.
Plants that receive sunlight in a green house can take more micromouls before co2 is required.
Under artificial lights I am pretty sure 1000 micromouls is maximum before co2 is required to go further.
There is probably a high chance that artificial lights have a more focused beneficial spectrum so although sunlight is able to hit the plants with more it isn't doing anything that is beneficial, the plants may just regulate themselves differently under the broader spectrum.
More research is required but I pretty certain there is a way to increase productivity without co2 and just with a different spectrum.
My own measurements show 3-5 degree F diffs between lst and airtemp, when air temps are mid- to upper-70s, under all three types of white leds.
So, this approach certainly has its benefits for white leds...
Do you use one of the atomizer donuts in this room? Was there condensing water? This could have an effect on the LST and keep the leaves cooler.
To avoid condensation inside my grow area's I increase the humidity in my lung room to 70-80% to get 60-70% inside my grow area. I also add the CO2 there... Doing it this way I can keep my windows closed over the day and open them only at night. When the windows and doors are closed the humidity increase automaticly by the amount of water evaporated by the plants. That's more than enough humidity.. Sometimes I have even to use my dehumidifier to keep it at a certain level.
My lung room has 18m² and my grow area is only 0,84m² and it takes only around an hour to get the RH where I want it.
Only in early veg when the plants are small I have to add humidification but as soon as the area is almost filled with green thats no longer neccessary.
Is there a way to use the lung room this way and keep the level higher in the whole room? You have 6x as much grow area, the plants should easily create more vapor than neccessary.
The only down side is that water is condensing at the colder windows(dew point) and I have to direct a fan on the windows to avaid it. But its only a small 120mm PC fan, so not a big thing..
As long as the lung room dries one time the day you can avoid getting mold easily. When windows at "night" are open humidity goes down to 50-60% and till now I've not found any mold.
(knock-knock-knock)
It also saves a lot CO² and the Oxygene level also increase over the day when you keep the room closed/sealed.
Its maybe worth a try .. if its possible..
Well, right now the plants are too small to produce enuff humidity on their own. And, yes, there is some condensation on the walls, due to diff in temp outside vs inside each tent (cooler outside).
So once again Dr. @Randomblame nails a long-distance diagnosis.
As for the fix, i could bump external rh setting to 70% from 60%, which i’ll try. The room containing the tents is so much larger than the tents, and its rh is difficult to hold that high.
The best way i’ve found so far, to hit rh target, at this stage, is with a vaporizer inside each tent. So it’s constant battle to get Goldilocks balance between temp and rh. I tend to err on hitting rh over temp.
After the plants have enuff leaves, the issue reverses, but is way easier to deal with. I was just getting to that point, before i topped these girls. Once i get done training, life gets easier.
You probably recall the nute issues i had with the green crack, during training, last grow.. This time i have more capability to boost rh in the tents...so, some progress made....
I just picked up a 4100k bulb to see how it does alongside the 2700 k QB 288's I was running a 3100k CMH prior and it was doing great but wanted a more blue-leaning spectrum and the bulb was running on 2 years old.