Please look at these and let me know what you think could be the issue

[Farmall]

this was on a hydroponic grow of 6 specimens under 3k LED(1000w at the plug) 3-1000 WATT covering 2 specimens each with a 20gallon reservoir with 5 gal plant buckets with very active air stones. Using General Hydro trio, changing nutes weekly and just entering 4th week flower. It occurs at the very lower leaves, shadowed by most of the upper growth. Some leaves are 8-9 inches and some are under 3 inches wide. In addition to the GH trio adding hydroguard prior to the nutrient mixing and final ph about 5.9. Until 2 weeks after flower, ph would rise to near 6.2. Third week into flower ph seems to drop to 5.5 and 5.6 and always checking it to minimize lockout at this stage. Any educated thinking on these pictures?

after all the reading I have done....and it was a shitload of reading for months,books and books and online ... I can not figure it out from 3 or four possibilities considering where it occurs. It is in all 6 buckets

[Farmall]

Could not attach in previous post

[9fingerleafs]

Are you using RO water? Or tap water? Or well?? Anyhow if this is only in the bottom most shaded leaves then it’s very likely the plant decides to take they mobile nutrients to a more useful place where it gets light. It doesn’t really mean you need more nutrients it’s just what happens to old leaves in the shadow

[D.A.A.S.69]

Farmall, great answer from 9fingerleafs.

[Farmall]

Ok....it sounds good....certainly not looking to overdiagnose a problem....I am using well water with a 73ppm out of the faucet. PH of 7.5 which I lower to 5.8-5.9 in hydro. All mid to top leaves look like lush greenleaves. Buds are developed and growing bigger at that point. Much appreciated information ! The “ flowering stretch’ really took me by surprise. These ladies are near 6’ tall and almost kissing the bottom of the led fixture. I am surprised that those leaves are not burned. Going up the last 6” of ceiling.

[Farmall]

Soon as the lights come back on later, I will do exactly that ...thank you

[D.A.A.S.69]

Farmall, You are very welcome, ole bud !!
I hope you have a wonderful harvest !!

[Toker1]

I typically shoot for a PH of 5.5 in DWC. Then let it swing up the 6.5 before I adjust it again.
Are your LED’s the 3w chips or the 5w chips?

[Farmall]

They are 5w.....what does that mean ?

[Toker1]

Well 5 Watts is how much energy gets transferred in a specific amount of time. Specifically in the form of heat. It’s referencing how much energy each diode receives.
5 w chips have good light penetration, but can cause light/heat stress if not far enough from the canopy.

[9fingerleafs]

So those king led with 10watt chips are even better/stronger??

[Toker1]

Never used anything above 5w before...so I can not comment. What I can say though is that there is always a point of saturation that leads to diminished returns.

[Farmall]

That distance thing has created difficulties since the LED Hydro was started. As seedlings they were too far and stretched.. As adults, the got to be too big in flower and I had to tie them down away from the light.