Mh/hps vs Led

[Aqua Man]

Yeah in a sealed setup you need AC and dehumidification. It's a must.

 

[TaimerPots]

With bottled I don't feel like you need to vent. If you want to it won't hurt to vent at night and that's plenty

Control just arrived, anything else needed to enrich my space?

 

[Aqua Man]

Have a dehuy, ac, heater and humidifier?

 

[TaimerPots]

Have a dehuy, ac, heater and humidifier?

I have a humidifier, I dont think I'll need ac/heating. I only grow during the winter and even when I ran my 1000 watt hps the hottest it got was 78°. I've been reading that humidity goes up with the use of co2 and a dehuy may come in handy

 

[growsince79]

IDK prolly 2 feet or so, I go by lumens so right now there getting around 30k @ i would say 2 feet with 50-75% intensity, hard to say with these fuckin mars lights..

So for guys with limited ceiling height,MH or hps is a better choice.

 

[LittleDabbie]

So for guys with limited ceiling height,MH or hps is a better choice.

I don't care??

Run whatever you want?

 

[growsince79]

I don't care??

Run whatever you want?

I thought hlg said their 100w could be 1 ft in flower. Hope I didn't get that wrong before I bought.

 

[TaimerPots]

Maybe someone can answer this question. I see a lot of people saying 80° is good for led, anything wrong with lower temps? Any negative effects from being in the low to mid 70's?

 

[Aqua Man]

Maybe someone can answer this question. I see a lot of people saying 80° is good for led, anything wrong with lower temps? Any negative effects from being in the low to mid 70's?

Led generally has lower IR and in turn leaf temps will be lower. Ideal leaf temps for optimal photosynthetic rates are around 75-77f. So generally room temps if around 80-82f are likely to put leafs temps in this range.

Leaf temps are more important than room temps

 

[Milson]

Led generally has lower IR and in turn leaf temps will be lower. Ideal leaf temps for optimal photosynthetic rates are around 75-77f. So generally room temps if around 80-82f are likely to put leafs temps in this range.

Leaf temps are more important than room temps

Where did you get the 75-77 number? That was what I'd had in my head as well, but I saw this paper from Black Dog LED where they made an assumption that you want LST at around 87! And I have seen this a couple other places too. I am currently sitting at about 80 for the tops of my plants (except one head that is higher and at 84 according to my IR gun).

Not trying to challenge you, just trying to sort out my sources here.

 

[Aqua Man]

Where did you get the 75-77 number? That was what I'd had in my head as well, but I saw this paper from Black Dog LED where they made an assumption that you want LST at around 87! And I have seen this a couple other places too. I am currently sitting at about 80 for the tops of my plants (except one head that is higher and at 84 according to my IR gun).

Not trying to challenge you, just trying to sort out my sources here.

Your talking about with CO2. I got it from many studies I have read over the years.

 

[Milson]

Your talking about with CO2. I got it from many studies I have read over the years.

Ah okay, I must have missed that with the Black Dog study. Thank you.

 

[4TREESCANNABIS]

You can get great results with LED. The electrical cost is 50% less and the HVAC needs are 40% less. Both yield and cannabinoids have gone up for us and our customers. Check our YouTube video at:

On a business sense, it makes sense to go with good commercial LED lighting. HVAC costs can be a lot on big facilities and electrical bills come in every few months so why not have them lowered? On a smaller tent growing scale or basement grow it makes sense there too with the lowered BTU (Heat) from each light and lower AMP draw combined with the ability to go much closer to the plant, which basements and tents kind of need.

 

[Aqua Man]

Ah okay, I must have missed that with the Black Dog study. Thank you.

They also note that leaf temps are higher than ambient temps... I just don't see this being possible in almost all cases. I think there was lack of account for wind and transpiration.

Look at the last post it clearly shows he is 6-8f cooler than air temps and in blackdogs study under led they are much higher than ambient temps. Which lines up with my experience and many other studies I have read

I never really counted that study as accurate and I never dug into what may have been the difference.

 

[Milson]

They also note that leaf temps are higher than ambient temps... I just don't see this being possible in almost all cases. I think there was lack of account for wind and transpiration.

Look at the last post it clearly shows he is 6-8f cooler than air temps and in blackdogs study under led they are much higher than ambient temps. Which lines up with my experience and many other studies I have read

I never really counted that study as accurate and I never dug into what may have been the difference.

So they were measuring ambient temp throughout the room, not the air right next to the plant. Hence why the temp was higher. Obviously the lights provide measurement problems for ambient air temp measurement, so what they did makes sense.

Or am I just totally off on what you are thinking about here.

 

[Aqua Man]

So they were measuring ambient temp throughout the room, not the air right next to the plant. Hence why the temp was higher. Obviously the lights provide measurement problems for ambient air temp measurement, so what they did makes sense.

Or am I just totally off on what you are thinking about here.

Ahh I see now.

 

[TaimerPots]

It's all new to me, before, I never used co2 and was taught to keep temps in the mid 70's. I was always taught that a plant slows its growth and concentrates on keeping itself cool with temps in the 80's, I was also taught that you can get away with higher temps in a co2 enriched garden. So needless to say this discussion is greatly appreciated.
The research I've done so far suggest you must meet the trifecta of light, nutrient and co2 to obtain the benefits of co2. If your light isn't strong you dont need co2, if your light and co2 arent good there's no point in playing with the ppm of your nutrients, you'll never achieve explosive growth.
I'm still going to shoot for temps in the high 70's if my humidity levels arent too high and focus on keeping the co2 levels around 1500 ppm. If I dont see anything better than normal I figure I can play with the vents to achieve a higher temp.