Opinions on adding 660nm

Rahz

Rahz

Well-Known Member
Humple said:
Well, it was bound to happen eventually - just like building and upgrading PCs, the Gear Acquisition Syndrome has finally kicked in, a year or so after completing the first of my QB120 fixtures. Folks who know me on this forum can probably recall the skepticism I've expressed around "spectrum-tuning", but despite my doubts, I am absolutely open to the idea; hopefully we'll soon see more data on this, as more peeps run the newer products, like the QB96 and the stuff from ChilLED. All that said, I must confess that my main motivation is just the old itch to play around - I'll consider it a bonus if I see measurable, positive results.

So this is what I'm currently working with (times two): 4xQB120s at 3000k, maxing at 250 watts, in a 31"x31" tent. Here's a pic of one of the fixtures, but the two are identical.
View attachment 4222610
The dimensions are 21"x26".

So the first question is: how much 660nm would you add? I've seen recommendations for 8-10% of the total white light, but I don't know if that approach has a strong basis. But using that as a starting point, the first solution that comes to mind would be a single 130 degree QB11 at 20-25 watts, run down the center of the fixture. The biggest problem I see with that is spread. By the end of flower, I have buds practically kissing the 120s, so at that point, the 660nm wouldn't be hitting much of the canopy. (Note to HLG: the size of new far red strips would be perfect, if only I could get them in deep red! They could be attached in a cross formation, but distanced evenly across the light.)

Another option would be individual monos, like those solderless stars. The thing about using those is that I expect I might have to modify my frame by adding little sections of flat bar. I suppose it would be feasible to attach the diodes to the existing frame, but I don't know if doing that would allow me to achieve the optimal spread (though it would have to be better than a single strip run down the center).

Opinions? Suggestions? Corrections? What would you do, and how would you do it?

Thanks, peeps!
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I don't know much about what's available in strips but I suggest seeing if there are high CRI low K options. It could significantly boost the reds without affecting the absolute blue values much. Start with 15 par watts per foot from the boards in veg or around 750 PPFD and then turn on the strips to boost the overall output to 1000 PPFD at flip, maybe maxing out at 1250 PPFD mid flower, or adjust both so you alter the red ratio while PPFD remains steady.
 
hybridway2

hybridway2

Amare Shill
Humple said:
Not really that interested in adding UV at all, to be honest. My understanding is that UV LED isn't quite there yet when it comes to price and longevity, and the reptile bulbs would be quite the hassle in my space. Also not super keen on the idea of exp88osing myself to the radiation! Probably just being paranoid, but the weed I'm growing is plenty strong and tasty, so why take the leap?
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I'm pretty ddiissapoointedd myself that some of the top manufacturers havent incorporated at least 380-420 nm. Add 2 extra & run them super soft to get them to last,, no? I mean who's really full spectrum w/o at least some violet?
I agree with YODA there.
 
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Old school grower

Old school grower

Active Member
Unfortunately no. At AliExpress and I know what your thinking but I've never had any problems. I have already received Royal Blue 450nm, Far Red 730nm, Deep Red 660nm and a few 620nm all Cree Xpe ×4 @ 12v.
 
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