What's going on?!?

So can anyone tell me what's going on with my plants? Can't seem to figure it out.

We assumed it was N toxicity and decided to flush 10 gallons RO (with clearex) through each #7 pot. Followed by 1.5X strength nutrients (proprietary organic blend) to rejuvenate the coco. These pictures are about 10 days after the yellowing began and leaves are starting to die off as shown.

1000W Double Ended about 6ft from canopy.

Temps are consistently 72-74°.

Currently at beginning of week 4.

xjamester said:

So can anyone tell me what's going on with my plants? Can't seem to figure it out.

We assumed it was N toxicity and decided to flush 10 gallons RO (with clearex) through each #7 pot. Followed by 1.5X strength nutrients (proprietary organic blend) to rejuvenate the coco. These pictures are about 10 days after the yellowing began and leaves are starting to die off as shown.

1000W Double Ended about 6ft from canopy.

Temps are consistently 72-74°.

Currently at beginning of week 4.
View attachment 3679092 View attachment 3679093 View attachment 3679094

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people need more details to help properly but to me they look hungry tbh

And these photos are under the HPS lamp? They don't look at that bad to me what strain is this, is it a Calcium hungry strain like OG?

Edit: Also you didn't tell us what nutrients