Introducing CobKits.com - specializing in DIY and Citizen COBs

CobKits said:

you could bolt a quantum to the top of your case. they run up to about 50W without heatsink and is a good call for that application

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subb said:

Awesome, that sounds great.. why don't people use these more than COBs with heatsinks? Is there a downside to them?

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subb said:

I'd love to pack in ~150w in my veg (50w per square foot) - is that a bit overboard?

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CobKits said:

theyre just a new concept in the last 2 months


yes, esp with high efficiency chips like that. 40W/SF is a lot, esp for veg where you hit the DLI on long days

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CobKits said:

looks more robust than a power strip. the molded extension cords with the 3 plugs on the end work as well

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subb said:

Awesome, thanks for the info! I'll be reading about quantum boards for sure.

Sorry, possibly dumb question but what does DLI stand for?

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subb said:

Awesome, that sounds great.. why don't people use these more than COBs with heatsinks? Is there a downside to them? I'd love to pack in ~150w in my veg (50w per square foot) - is that a bit overboard? I know it depends on a lot of factors but I've just read that 50w/square foot was sort of the LED "max" with diminishing returns after that. I don't even have to go that high.. I don't mind vegging longer, my flower chamber is the real powerhouse, I just wanted the veg chamber to be on par with it.

Thanks for the help!!

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thetr33man said:

Aim for 20 w/sq veg and 30-35 flower. Ive seen some nice plants grown full circle under 20w/sq... More than 35 you really need advanced techniques to benefit imo.

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shadow_moose said:

35w happens to be current measure to approximate about 1000 ppfd with current high end tech. Obviously, calculating average PPFD when you have your LER/QER numbers is better, but I just want to point out that watts/square foot is a variable measure with no set zero point.

That being said, "advanced technique" in this case refers to intense controlled environments, right? That means running CO2, controlling temp and humidity perfectly, probably running high performance synthetic nutrient solutions. Not really advanced, just a pain in the ass to do right and quite costly.

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thetr33man said:

Yeah, thats what I meant, to benefit Id say youd need to be an advanced enthusiast or professional. Obviously w/sq is a very imperfect measure, but still gives people a general idea and is easy to calculate and understand. On a totally different topic. I wonder how much putting a couple rats in a cage under your plants in a tent would boost CO2 levels... haha

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shadow_moose said:

Rats won't boost CO2 levels. The only way to artificially boost CO2 is through a sealed grow space and tanks.

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Godfather420 said:

I think I may have made an error in my ordering. I was planning on running 3 citi 1818's pinned down with BJB's wired in series, driven at 1.4A off a hlg240 c1400b. Forward voltage max on these BJB's I just read is 60v 3A... UH OH!

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Godfather420 said:

@CobKits Hell yeah! No swap necessary! 10-15v over....NBD.

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Godfather420 said:

ahahahah I know you think water cooling is pointless ()

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Godfather420 said:

I've got an extra water cooled housing prototype, (pressure tested to 100 psi, tig welded so no towels need) here if you want it for testing..The price... free.... Pm me for details. Thanks for helping all of us.

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sixstring2112 said:

14 w per sq ft and around 390 to 400 ppfd average on the top half of the plant seems to work fine

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