im using propane- do people have opinions on propane generator vs straight co2? Im gonna use it as heat for the house now that its cool but what are opinions? in symmer i had to use alot of ac to cool it down.
It’s 3.42 BTU/watt of light. If you add burners, it throws off the equation from the added heat. You just have to overbuild and hope it keeps your rooms properly cool and dry.
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for example tho - your equation doesnt take into account a cold basement in winter. real life will eqate that into how i deal with it. theres a new fan that has a heat and humidity monitor to turn it on and off and ill get that and see.
1 watt is 3.42 btu’s of heat no matter how you look at it.
Your cold basement isn’t consuming energy so it’s not part of the math
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im new to high dli and co2. i got confused. i am taking hvac into the thing accidentally. if i was building a space id follow numbers, im renting and have to wing it.
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Get yourself a mini split
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i really want one, but im scared the moment i modify the house ill get inspected. my landlord has been great, they visited 2x in ten years but i get annual semi annual inspections from the govt and they do dumb shit like look in my closets to check if the lightbulbs work? and always find a problem like a hole in a window screen? its called an anti crime inspection program? Ive done the humboldt shuffle like 20 times. last year the inspection wasnt gonna happen due to covid- then they are like NEXT WEEK im like chopping down weed and that stunk.
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I never took physics, so all I understand is layman’s terms, but a big concrete basement will act as a cold sink in the winter, sapping out the heat generated by the grow, usually hps lighting in the old days. Back then I thought you had to be in a basement to grow, truth is it was just a lot easier.
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Sure it’s a big heat sink, and that’s a benefit to the total heat load. But it doesn’t change the 3.42btu/watt math. That’s all I was getting at.
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How do I calculate the right balance ?
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Welcome, to the forum Tec!
For CO2, keep it between 1200-1400 ppm when PPFD exceeds 1,000 and 1400-1600 when PPFD exceeds 1,500. High Co2 reduces stomatal openness. And too much CO2 can significantly reduce transpiration (and nutrient uptake of mass flow ions), carbon fixation, photosynthesis, and so on.
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I had done some research on co2 years back and found a scietific article on wheat i believe. I think they referred to it as a class 3plant type and cannibus fell into same category.
They found 1200ppm daytime and no higher than 900ppm at night but 600ppm nighttime best. As thete are processes that occur day and night.
I find 1500ppm first 30days of flower and 1200 last 30 days and can be shut off last week or 2. Suppossed to ripen fastet last week without?
Anyways running 1500 all the way makes it airy and loss of smell.
All parameters have to be solid or u wont get the benefit
You want to increase metabolism as much as possible while still allowing the plant to transpire. Start low and work your way up. I like my room between 50-70RH and 85+ degrees. 2000+ co2 and 2.5ec. this give me a vpd in the 1-1.7 range, and sometimes I even sneak out of range and it’s really nbd. Just play around.
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I pretty much just follow the ppfd once in flower and keep it the same until i hit 1200 ppfd and 1250 ppm, then i keep it there until i start to turn the lights down again.
I want to try and get my ppfd up to 1500 the next run.
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Does anyone else use the photone app to measure your lights? I’m curious to see a side by side with a real meter. According to Reddit the app is pretty close now
Thank you for the answer
What if ppfd is lower than 1000? No need to supply co2 under 1000 ppfd?
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studies like that are kinda worthless. I could probably get a bigger yield on cannabis just not even budding it at all and doing a thick ass veg grow. It wouldnt be quality at all but may get a yield number. we arent growing for the max carbon matter.
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with good samsung led they are quite strong but dont spread much. If you are using aprox 600 wall watts over a 4x 4 space the ppfd crushes hps and lec and NEEDS co2 and some heat to work optimally- and then youll be crushing it. I rented a meter and measured and found 3 lights per tent for 1200 watts really is great. I have all lights and led crushes hps, mh, lec, and dual ended gavita. Its a different animal, I use different nutes and the temp is higher and CO2 they often need more phosphorous or start looking funny. Its so strong im still learning and if they get tall the 2nd tier buds are bigger than tops. I gotta keep the light further but sometimes run out of space.
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You’re welcome.
PPFD <400 = ambient CO2 (indoors can exceed 600 ppm)
PPFD 400-800 = 750-1000 ppm CO2
PPFD 800-1,000 = 1000-1200 ppm CO2
These are just rough guides. The important point is don’t exceed 1400-1500 ppm CO2 unless you provide high PPFD with optimized environment, irrigation, fertilization (incl. increased NH4), and dark period fresh air exchange (to reduce ethylene). And don’t exceed 1600-1700 ppm or so because you’ll hit the point of diminishing returns (lower photosynthetic rate and wasted CO2).
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Going 2000+ co2, what should I be aware