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LED and BUD QUALITY

Ca++

Well-known member
That is not proof of nute burn. Once you have been growing long enough you will figure this out. That happens whenever I start my fade using RO water. I also noticed it more when I switched to LED using the same feed as I did with CMH.. CMH never had it. I use an EC of 1.2. which is not a level that would cause tip burn. During fade is when I see that the most. It is not an issue to be concerned about.
I imagine it's K deficiency. Ca becomes harder to take from mid bloom, and while I have no explanation for this, the knock-on rationalisation is that K will follow. In some plants, heavy K at the very end is known to help. A feed recipe some sell to outdoor hemp growers. Though I see no proof, or wide acceptance that it's needed.
We are looking into the crystal ball here, but there is reason to think more K is needed, and that K is getting harder to take. The first signs will be dead tips, but they are not the curling up and back leaves of heavily salted plants. The pics have just been shared on this thread, for those that can see the difference. It's burning, but because of low water. Leaving salt accumulation, but you see things like loss of colour and turger, not 14th century footwear.
 

greyfader

Well-known member
full


lowest 3 will be silenced soon.. just continue
thank you! as you have noticed, canna t is officially trolling this thread right now. he fully understands that the thread is about LEDs and bud quality not LEDs vs HPS. we've had this discussion with him many times and he just keeps coming back and doing it again.

to everyone;

there is a thread entitled LED vs CMH vs HPS that is the appropriate thread for cheering for your team.

if you feel like bashing one light source over another please go there. everyone is sitting in a little circle playing whack-a-mole on the light sources they don't like.


please stop disrupting this thread.
 

weedemart

Active member
@Prawn Connery No. I estimated 4-6lbs per fixture based on the ppf output ,canopy surface and number of day to harvest. but yeah I realized I gave number of another fixture. anyway.
All indoors.

if you do the math like an amateur.

4*448g/1000w= 1.792g/w
6*448g/1000w= 2.68g/w with co2

not that hard to achieve with 3.15umol/s fixture , I do 1g/w with an old led @ 1.8umol/s no co2..... and thats because I intentionally limit my ''mass balance'' because my licence limit at 150g LOL

I will tell you how I estimate yield . It's once again coming from Bugbee. And it's very close.

gml greenhouse tarantula 1000w fixture

ppf 3227 umols
canopy surface 2.32m2(5sqf * 5sqf)
day to harvest 63

ppf/canopy surface=1391 umols/s/m2

dli= 1391umols/s/m2 * 3600s/h *12h/day = 60 mole/m2/day

cannabis on average 0.22g/mole/day/m2

.22g/mole/m2/day *60 mole * 63 day *2.32m2 = 1929g/1000w=1.929g/w

if you understand '' mass balance'' you can gain up to 50% yield with co2

1929g *1.5 = 2894g/1000w= 2.894g/w

So im sorry. it's 4.3-6.45 pound per fixture.
 
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weedemart

Active member
Just for fun , a REAL example of someone. and it correlate with REAL result.

ppf 19800
canopy surface 23.23m2
number of day 63

ppf/canopy surface=852 umols/s/m2

dli= 852umols/s/m2 * 3600s/h *12h/day = 36.8 mole/m2/day

cannabis on average 0.22g/mole/day/m2
.22g/mole/m2/day *36.8 mole * 63 day *23.23m2 = 11848g/448g/pound= 26pound

you should take the course @Prawn Connery

To get these number you need more than the fixture.
 
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Rocket Soul

Well-known member
Just for fun , a REAL example of someone. and it correlate with REAL result.

ppf 19800
canopy surface 23.23m2
number of day 63

ppf/canopy surface=852 umols/s/m2

dli= 852umols/s/m2 * 3600s/h *12h/day = 36.8 mole/m2/day

cannabis on average 0.22g/mole/day/m2
.22g/mole/m2/day *36.8 mole * 63 day *23.23m2 = 11848g/448g/pound= 26pound

you should take the course @Prawn Connery

To get these number you need more than the fixture.
To get these numbers you need a light which throws light only on the cannopy and not a photon on the walls. You calculate based on no optical light loss; every photon on cannopy. If this is based on HPS that is very unrealistic; we all know theres reflector losses and other losses with regards to hanging an omni directional light.
 

Ca++

Well-known member
To get these numbers you need a light which throws light only on the cannopy and not a photon on the walls. You calculate based on no optical light loss; every photon on cannopy. If this is based on HPS that is very unrealistic; we all know theres reflector losses and other losses with regards to hanging an omni directional light.
These numbers are below my minimum expectation.
Due to the common 2.44m dimension of timber (8 foot) and the 1m reach I like, I have made too many systems in multiples of 1 x 2.4 meters, with a pair of 6s over them. 500w per meter. It became my benchmark, rather than the 600w per meter more commercially accepted.

Using the 0.22g/mol/d I would only get 16oz per meter.
500x1.7=850umol.
850 x 60 x 60 x 12 = 36.7mol
37.7 x 0.22g = 8.074gpd x 56d's = 452g

There is perhaps a 2% chance of that 16oz. The expectation was 18oz, and reality 20oz. With my own (at home) doing about 22. I'm not adjusting these numbers for the occasional blunt tool, who just can't do it though.

What I have noticed, is some of these grams per meter/umol or whatever, are for a facility, over a year. They look a lot like this 0.22 which at first seems shocking. However a facility is a lot more than space for flowering plants. It includes parking. It's easy for me to look around a building. Look at the incoming power limitations, and start figuring alternate 12/12s with veg space. Then talk yield per meter of bloom. However, show me a leveled industrial park, with a transformer up a pole, and I'm going to have a little pause. This 0.22 comes into focus.
 

Rocket Soul

Well-known member
These numbers are below my minimum expectation.
Due to the common 2.44m dimension of timber (8 foot) and the 1m reach I like, I have made too many systems in multiples of 1 x 2.4 meters, with a pair of 6s over them. 500w per meter. It became my benchmark, rather than the 600w per meter more commercially accepted.

Using the 0.22g/mol/d I would only get 16oz per meter.
500x1.7=850umol.
850 x 60 x 60 x 12 = 36.7mol
37.7 x 0.22g = 8.074gpd x 56d's = 452g

There is perhaps a 2% chance of that 16oz. The expectation was 18oz, and reality 20oz. With my own (at home) doing about 22. I'm not adjusting these numbers for the occasional blunt tool, who just can't do it though.

What I have noticed, is some of these grams per meter/umol or whatever, are for a facility, over a year. They look a lot like this 0.22 which at first seems shocking. However a facility is a lot more than space for flowering plants. It includes parking. It's easy for me to look around a building. Look at the incoming power limitations, and start figuring alternate 12/12s with veg space. Then talk yield per meter of bloom. However, show me a leveled industrial park, with a transformer up a pole, and I'm going to have a little pause. This 0.22 comes into focus.
Id tend to agree, a pound per m2, from 500w even if hps is a low expectation. Incidentally, an error snuck into to your maths; you went from 36.7 to 37.7 one line under but i dont think it changes much.
 

dogzter

Drapetomaniac
Just for fun , a REAL example of someone. and it correlate with REAL result.

ppf 19800
canopy surface 23.23m2
number of day 63

ppf/canopy surface=852 umols/s/m2

dli= 852umols/s/m2 * 3600s/h *12h/day = 36.8 mole/m2/day

cannabis on average 0.22g/mole/day/m2
.22g/mole/m2/day *36.8 mole * 63 day *23.23m2 = 11848g/448g/pound= 26pound

you should take the course @Prawn Connery

To get these number you need more than the fixture.
You are adorable!
So when will you be taking over the industry?
 

Hammerhead

Disabled Farmer
ICMag Donor
Veteran
So what are the top performing brands of lights in the commercial indoor space at the moment or are they all performing similar now? The industry has been moving so fast it’s hard to keep up…

The only LED I'm interested in trying is the Grandmaster Borg series.. 1500 watts with a Potentiometer on each channel for manual spectrum control.
 

Ca++

Well-known member
Id tend to agree, a pound per m2, from 500w even if hps is a low expectation. Incidentally, an error snuck into to your maths; you went from 36.7 to 37.7 one line under but i dont think it changes much.
Oh damn. My mind was still on the fact I rounded from 36.72, and if the 7 really mattered for this exercise, for anything other than being corrected :)
I made it worse.. but yeah, not really important. The plants containment within that space is more questionable. A few percent of the yield was from extra space, surely. But this was only ever a guestimate. With the containment of a tent, I don't think any differently. Though I always fall close to the lower end of my expectations in tents. I have never once pulled off an outstanding tent grow. Not judged beside my grows without tents.
 

weedemart

Active member
Oh damn. My mind was still on the fact I rounded from 36.72, and if the 7 really mattered for this exercise, for anything other than being corrected :)
I made it worse.. but yeah, not really important. The plants containment within that space is more questionable. A few percent of the yield was from extra space, surely. But this was only ever a guestimate. With the containment of a tent, I don't think any differently. Though I always fall close to the lower end of my expectations in tents. I have never once pulled off an outstanding tent grow. Not judged beside my grows without tents.
Actually you calculated the wrong ppf output and you forget to add the canopy surface.so its all wrong. :(

ppf = 600w hps @1.8umols/w = 1080 umols/s

day= 56

canopy surface = ?m2

ppf/canopy surface = ?mole umols/s/m2

.22g/mole/m2/day *?mole *56 day *?m2 = gram

example for 4x4 canopy surface.

for 16 sqft(4x4) = 1.5 m2

dli=1080/1.5= 720/umols/s/m2 * 3600s/h * 12h/day =31.1 mole/day

.22*31.1*56*1.5= 574gr

574gr/600 = .95gr/w

up to 862g = 1.45gr/w
 
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Ca++

Well-known member
Actually you calculated the wrong ppf output and you forget to add the canopy surface.so its all wrong. :(

ppf = 600w hps @1.8umols/w = 1080 umols/s

day= 56

canopy surface = ?m2

ppf/canopy surface = ?mole umols/s/m2

.22g/mole/m2/day *?mole *56 day *?m2 = gram

example for 4x4 canopy surface.

for 16 sqft(4x4) = 1.5 m2

dli=1080/1.5= 720/umols/s/m2 * 3600s/h * 12h/day =31.1 mole/day

.22*31.1*56*1.5= 574gr

574gr/600 = .95gr/w

up to 862g = 1.45gr/w
No.. I think I got it right.

When you worked out 'the real someone's grow. You didn't account for the 28 days the lights were not turned up. Starting at 40%, so the dli over an 8 week period, is 15% lower.

I'm doing high school maths at the moment. I'm on page 4 of so many pages, it's a hardback. I don't want to know. Already I'm at long division of decimal numbers, and it's only worth a 3. I need a 6 at least, and this book must reach 100. School sucks.
 

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