Spyder7

@DeadwebsiteBoringcommunity,you said ppfd = more yield "simple as that." All I did was point out that it actually isn't that simple and the "I'm just gonna grow more than you" is not a counter argument unless you are like 5. Whatever dude.

@DeadwebsiteBoringcommunity, in theory, "ppfd=yield" until you take into account other factors. One factor is the growing room. If you put my light into a black nylon tent without the reflective walls, so that you had zero reflectivity, you're not going to get the same yield I'll get in a grow tent with mylar even though the PPFD is the same. And I've read that the mylar in a modern tent is so good that it multiplies your PPFD by 25-33% depending on type and how much its reflecting (how close it is to the light). Other factors are humidity and heat. Both can impact yield all by themselves. So can grow techniques and nutrients. So you're being reductionist to the point that you're wrong - there are too many other variables that have nothing to do with pppf but will impact yield. There's truth to what you say to a point, but not to the degree you make it so I disagree. That's the problem with reductionist reasoning: it is too simplistic and it does't take into account variables that matter.

@DeadwebsiteBoringcommunity, Its not a pure COB. These are the actual specifications: Product Specification [LED Qty] 28pcs 5w Bridgelux/Epileds + 1pcs 10w Cree COB [HID Replacement] Replaces 150W HPS/MH [Input Voltage] AC100-240V [Avg. Power Draw] 62±3W [Core Coverage Area] 1.5x 1.5ft at 24" Height [Max Coverage Area] 2.0x 2.0ft at 24" Height [Dimensions] φ6.9x 2.4 inches [Item Weight] 2.1lb [Lifespan] 50000h [Frequency] 50-60Hz [Warranty] 2 years So there's a single 10W Cree COB in the center surrounded by 28 mostly red and blue lights. I think there's a single green LED. And I believe it has one or more UV and IR LEDs within that count too. That's how it produces that spectral ratio.

@DeadwebsiteBoringcommunity, good question. The manufacturer gives a spectral graph and a light count. They specify the ratio as 53.4% Red, 36.9% blue, 9.7% green. I don't think its short because of a lack of blue spectrum. CKS says this is a dwarf strain, and I began training it (first with LST) at 5". Then I super cropped everything but fan branches later and topped it (accidentally). So I think its short mostly because of genetics and because daily plant training has kept it short. Also, the HST really seemed to put the breaks on growth and the plant seemed to put its energy elsewhere as every time it got an inch or two of fresh growth somewhere during the first week of the stretch, I super cropped and then LST'd. And this week, despite plans just to LST, I'm still super-cropping to control height, as it can work better than just LST (I'm using both). So I think its genetics and training.

@DeadwebsiteBoringcommunity, I've learned a lot about LEDs and this great little light since my first grow. I'd forgotten how strong it could be and burned some leaves early this grow, but since then I've been managing it more carefully. Looking back at my first grow now, it took as long as it did largely because I was too cautious with the light; this grow I've had it more "in the zone" I think, and this plant seems to be maturing faster. It still won't be ready in the 7 weeks CKS advertises, but I'm thinking this one will finish within 10-11 weeks (total), which I would be pretty happy with. Completely dialed in, I think it could pull close to a gram per watt from the wall, or close to 2 ounces, though it might take a high yielding XL strain to see it. But I'm hoping for at least 45 grams, which would put it on par with what an equivalent HPS light could do, and I think its attainable. I didn't have a scale to weigh my last grow, but I will have one this time before its ready to harvest.