30 ounces from a single ended 600 watt HPS in a 4x4.
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Or 18 ounces from 260 watts of LED's in a 3x4 area.
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Or this mornings upload to YouTube
Nice, and yep that's 1.5/ft2 and 1.875/ft2 both figures under 2lbs per 4x4. That's what I'd expect to see.
Hard to believe. I know, i have been challenged on this grow before and i appreciate that you trust those numbers. But in the end they aint mine, theyre my buddys. He wont let me post pics (comercial and very "red" situation), but this run being the last he might change his mind. Maybe over pms i dunno. If i get them, ill get them to you.
On the light situation: we use mainly fotop boards, around 2000 lm561c chips per m2 run just around nominal. The form factor: chips are very spread out, evenly over around 7.5 square foot of boards.
Compare to a hlg550: almost 1200 chips to 16 square foot of cannopy, board realestate is just under 3 square foot, a little bit more area if you measure the full sink-sheet. The hlg needs almost 2 foot hanging height and is normally used at a 30w/foot. How much do you think you lose to the walls at 2 feet hanging compared to 8"?
This kinda spread out fixture penetrate deeply due to the form and the falloff in intensity does not follow inverse square law (its not a point source). I recommend trying it, cover your cannopy in board leaving only 5-6 inches between: it will give you even spread which you can dial up or down by raising and lowering.
Spd: 2700k 90 cri and 3000k 80cri. 2700 did better at similar power. We also had 2700k 80 cri that was sameish as 3000k.
Why do i think we can do more:
We defoliate and prune on day one. The only thing left is where we want new growth and buds. Any bud carrying branch is grown in stretch, what goes into flower is just skeleton.
That way our buds are grown on brand new and more vital growth. Also it allows us to control how much stretch by light starving a bit during stretch.
The thing is: even if we clean all theres allways some little sucker branch with a bud. The size of these buds indicate how much energy the plant has: if they are really big in comparison to the branch: the plant had more energy than possible budsites, and should be able to do better with a different pruning/stretching. That time we had huge lower buds on flimsy lowers. This most time recent the sucker buds where even bigger but yield is lower; my buddy overdid the defo/prune a bit and put smallish plants in.
JSheeze: i have to admit im not sure i understand you, those 20 zips/8' are your numbers or someone elses numbers you find impossible? I jumped in without reading the whole thread. I just dont find it impossible; we kinda stumbled into the same ballpark and im im pretty sure we arent the greatest growers ever, thats why i say hard and lucky, but not impossible.
There's been a couple guys on here saying their pulling 2lbs+ with 450W out of a 4×4. Id have to go back and check who.
All I've said is that cheap LED or cheap HID is best value when it comes to cost/yield. This is due solely to the fact that electric is cheap and when electric is cheap Gpw means zip. It becomes grams per ft2.
When I showed my 535W for $35 pulling 14oz from a 2x4 with no CO2, outlining the fact that you don't need to buy anything expensive, I got all sorts of pushback. When I delved into their claims it was obvious they were just jaded because the figures were outrageous.
I would encourage a skim
The most recent was 2.5lbs out of a 4x4 with 450W I do believe.
I'm not saying the one off grow can't be great (that's how I felt about the 14 from 8ft2), but on average I find it hard to believe any LED grower pulling 2lbs+ from a 4x4 with 450W.
I've been doing this awhile whether for myself or others so I kind of know the limits of yield per area, 2oz/ft2 is getting max of what I've ever been a part of.
No it wasn't. You were the one who actually mentioned a g/W metric.
Besides, it depends on what's important for a grower which is more important. If you are limited on watts then g/W is the most important one. If you have only a small space available then g/m2 would be more important. For some (if not most) growers it might not matter at all.
The one metric that is really utterly useless is the yield/plant. Especially when it's the sole figure. I've only gotten between 25g and 250g per plant, but you could get several kilograms per plant if you want to. I've seen people growing sequoia like cannabis trees outside.
Either way you were the one who started posting some useless metrics pretending that proves anything when they are in fact rather average.
It's much easier to go well over 600g/m2 (2g/sqft) with leds than it is with HPS and such. You will then have a much higher yield and return per m2.
Also $0.10 per kwh is extremely low. Don't pretend that that is a normal price for everyone. But even then the ROI is not determined by that $35 alone. You need to factor in the electricity and that's still a massive amount more than that $35. If you go for an investment period of 3 years then the electricity would still be over tenfold that. And if you yield say 10% less per m2, then the "cost" (lost revenue) of that could be a hundred times that $35 "investment".
You need to quit copying what I've said like its something I don't know. All that drivel about situational, lol ya, go back and read what I've said.
Ill try to explain a bit more for you, but then you need to reread and get a grasp for the numbers because you're all mixed up.
I don't think gpw is a metric that you should build your grow around but it can still tell you how effecient you are growing. There is a yield to effeciency threshold that gets crossed when reaching for 2.0oz/ft2+. If you're pulling 2oz/ft2 you normally aren't doing it with super low currents because the total light output is small even though the μmol/J is high. You get to a point where you literally can't put any more light at high effeciency because there's no room or there's not enough chips overhead to accomplish, at this point you are forced to drive the light hard to get the photons needed for the 2.0oz/ft2. But as you slammed the light to increase the total photon count the effeciency drops, so its hard to believe 2.0gpw at such a high yield. MJ doesn't increase yield lineraly. So it takes a considerable amount of light to increase from 1.5 to 2.0 per ft2. That's why 900 PPFD is target for optimal efficiency, after that you just have to really add tons of energy to the system to increase the yield. If your using CO2 and getting over 2.0/ft2 then your not under 900 PPFD.
Limits are made to be broken but its just a bit tough to fathom.
@Rocket Soul might be achieving these around 2lb/ft2 figures, but I'm still skeptical though after he outlined the fotops, I see he may actually have the chip count to have the high umol/s and high umol/J equating to (with luck) 2lbs from a 4x4 at lower wattages than I've ever seen before (not sure exactly what the total wattage was but much lower).
Still 2.5lbs from 450W is ridiculous. Even RS was only 2.11 and with all sorts of setup, CO2, ect, not buying 2lbs+ from a 4x4 with cob at under 450W. Doubt others are running grows with the chip count RS is using.
$0.10/kWh is pretty par for the course in the states. I've lived all over.
