Whatever happened to...

Gquebed

Well-Known Member
When i first looked into COBs and then bought em, back in 2016, guys here were talking about pulling 1.5+ GPW with their COBs. I dont see that talk anymore... is that because such is just accepted as normal now or is it because nobody is really hitting those numbers?
 

Chronikool

Well-Known Member
When i first looked into COBs and then bought em, back in 2016, guys here were talking about pulling 1.5+ GPW with their COBs. I dont see that talk anymore... is that because such is just accepted as normal now or is it because nobody is really hitting those numbers?
Nah..itz just that nobody growz here anymore.. More about theoretical numberz... chasing that elusive perfect spectrum and spitting out 'witty' comebackz to the previous comment. ;)

In all honesty...i dont see many familiar faces here from then...(shrug) :)
 

Rocket Soul

Well-Known Member
I believe that g/w is getting more and more irrelevant. Higher g/w seema to go with lower yield per area.

We were surprised we scored 2 per w on our first proper mono crop. But the totals or per square foot were still solidly in normal territory: 60g/square foot. Thing is now you can relatively easy grow with 30 w per foot or even less.
 

ttystikk

Well-Known Member
That was under hid.

Under cobs im not even close to 1 gpw.
I second @lukio on the temps; under LED the ladies don't get anywhere near the infrared heating that they do under HID lighting so bumping up ambient temperature is needed for proper transpiration. Another change might be to add epsom salt for the magnesium if you don't already.

I generally recommend 30C. Lukio kills it so I'm curious what he runs at?
 

ttystikk

Well-Known Member
Running at about 80f.

They do fine up till about week four or five... then deficiencies start the show up.... and they slow right down.

I'm thinking that my newts are too strong for the intensity of the light....
Deficiencies aren't usually the result of your nutes being too strong.

There's a balance.

What's your light intensity, in W/ft²?
 

Gquebed

Well-Known Member
Deficiencies aren't usually the result of your nutes being too strong.

There's a balance.

What's your light intensity, in W/ft²?
I was just reading that if the light is too intense, plants dont use as much nutes, but they need the water because transpiration increases. So...you create a lockout situation...

Res requires top up, while ppms rise and ph is more or less static. ???

I dunno... im just learning hydro now. On my second run as soon as clones are ready...

1300 cob watts over 8x4 area. Had to back them off to 22" inches above the canopy...
 

ttystikk

Well-Known Member
I was just reading that if the light is too intense, plants dont use as much nutes, but they need the water because transpiration increases. So...you create a lockout situation...

Res requires top up, while ppms rise and ph is more or less static. ???

I dunno... im just learning hydro now. On my second run as soon as clones are ready...

1300 cob watts over 8x4 area. Had to back them off to 22" inches above the canopy...
That situation results from high transpiration.

1300W / (4x8=32ft²) = 40.625W/ft²

That's a lot of light. Raising temperatures will help the plants transpire more and get the nutrition they need.

Do you supplement with CO2? With those light levels it would be leaving a lot of you'll on the table if you didn't. It would help the plants utilize more nutrients as well.

What's your RH? Proper transpiration requires stomata to be open. Low RH inhibits that. Excessive RH would also lead to deficiencies because it directly blocks nutrient uptake through transpiration.

With those light levels, you're running a very high intensity grow. All parameters really need to be on point to prevent problems and get the most out of your setup. When everything is right, I see no reason why that setup couldn't be producing over 4# a run.
 

ttystikk

Well-Known Member
You need to be 82-88° under white leds. Some people even run 90° but I dont like hitting that high. My area is set and holds at 86° and seems to be on point. And also Epsom is your best friend under whites
Mix that epsom salt into solution separately, using hot water! If it isn't fully dissolved it will flocculate with calcium and create gypsum, which is basically water INsoluble. Then you have both mag and calcium deficiency issues, no fun.
 

lukio

Well-Known Member
I generally recommend 30C
VPD yo! im usually around 28/82ishhhh i have struggled with lower temps in the past i think, for the reason you said but ive seen @Moflow grow in the arctic (his shed). probs a strain thing?

Deficiencies aren't usually the result of your nutes being too strong.
could be slight lockout from too much? maybe build up of salts, ive experienced this i think and flush a bit more now.

@Gquebed in water? and average ec? im feeding the lowest ive ever fed and theyre looking great at the mo...im on 0.85ec in flower in coco and 0.2 of that is mag of the epsom salt variety, pre mixed and into rez before anything else. ive only grown in coco, 1 way...lol.
 

Gquebed

Well-Known Member
That situation results from high transpiration.

1300W / (4x8=32ft²) = 40.625W/ft²

That's a lot of light. Raising temperatures will help the plants transpire more and get the nutrition they need.

Do you supplement with CO2? With those light levels it would be leaving a lot of you'll on the table if you didn't. It would help the plants utilize more nutrients as well.

What's your RH? Proper transpiration requires stomata to be open. Low RH inhibits that. Excessive RH would also lead to deficiencies because it directly blocks nutrient uptake through transpiration.

With those light levels, you're running a very high intensity grow. All parameters really need to be on point to prevent problems and get the most out of your setup. When everything is right, I see no reason why that setup couldn't be producing over 4# a run.
No co2. I have to vent heat for now, but co2 is the plan eventually.

My rh even through winter was decent. About 40% usually at 80f. I didnt want to raise temps beyond that to avoid vpd probs.

And youre right... lots left on the table. Im used to pulling close to 3 lbs in 8x4 and this run i only managed 2. Ouch. But... i will claim some success in getting through my first ebb and flow table run with no major problems. Or rather i didnt raze the whole crop. Lol
Im starting my next run now and plan to drop ppms a bit ... and dim the lights some... see what effect that has...
 
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Gquebed

Well-Known Member
You need to be 82-88° under white leds. Some people even run 90° but I dont like hitting that high. My area is set and holds at 86° and seems to be on point. And also Epsom is your best friend under whites
Hmmm....where is your RH at, at 86f?
 
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