Verbalistcommentedweek 122 years ago
Hey @PhunkyPhallus ! Appreciate your concern and I'll try to answer best as I can.
Okay, firstly this diary comes little behind as I chopped the plants down ~3days ago. I'll update it soon.
But yes to the subject. Quickly checked your diary and the board looks very much the same. Mine is KingBrite's 240W Samsung LM301b board. The board only has two different diodes: 3500K 'White' Leds and 660nm Red diodes. So the output color temperature (CCT) is close to ~3000K, which is then very reddish spectrum. 3500K diodes support narrow scale of blue wavelengths.
Plants can not utilize all that red light, even in full bloom. It's ofcourse strain depent, BUT when plant can't absorb all the light it converts into heat on the leaf surface (your tent/canopy temp wont rise tho) and plants start showing light/heat stress. Excessive red light also βforcesβ plants to transpire more which then creates nutrient imbalances and deficiences/excess symptoms may appear.
And I believe that was my issue.
During the veg I had a different 4000K temp led's and I ran them between 700-1000ppfd. Under the 240W led plants never looked happy when PPFD exceed 500-700.
And about lowering my ppfd near the end was because the buds started to show worse light stress symptoms more and more (foxtails & chlorosis)
When leaves starting to "pray" at a tight angle they're trying to cover the leaf surface from excess light.
With your plants I'd first try to dim the light down to 350-450ppfd which would result in about 30-40DLI with 18/6 or 20/4 light cycle. And start working way up from there. OR try adding some more blue light eg. CFL's for richer spectrum.
Our LED boards are mass products made in China. Indeed they're very strong fixtures, but the spectrum is not best designed for all plants.
Hope this helps at all! π If you've got any further questions don't hesitate to reply here or send me a DM.
- Verb
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