Light stress?

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Well-Known Member
Jan 11, 2022
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Week 4flowering everything was perfect . My ppfd was around 700, temps around 82F humidity 50-60%. Week 5 I decided to increase my ppfd to 850-900 . Temps 75F rh 50-60% leaf temps the same with room. Got some foxtailing, evaporated terpens. How could this be possible? My feeds are the same, run off tds showing me that I should give some more food but I don't . 850-900 should be great mid flower but not this time. My girls just don't like strong lights or it's the temperatures I decreased? Any thoughts?

Led lights
Tons of fresh air in the room
Good air circulation
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I've never had a plant that didn't like the light. As long as you're not frying them with temps like you can with HPS/MH lights, I can't see that being your problem.
After many hours of research my conclusion is that I got cal deficiency. Got some brown spots, purple on stems and few buds (no low light temps) growth slowed down and when cal is missing, plant tolerance to heat drops dramatically. Hopefully in 5 days they will bounce back. Until then, temps going.. Light power too .
You could get liquid calcium in several forms, the more various the sources the better. Avoid calcium nitrate this late in flowering. Calcium is one element that is beneficial to give excess of it but is a bit difficult to make soluble without nitrogen which makes it more costly. However it is worth it imo. The ratio of calcium to magnesium is good at about 2:1

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