Hydroponics Yellowing / Dropping and other things

So I have a Greentrees multi flow 2 gallon bucket system. 2 systems. Each system has 36 buckets connected to them. Each system is connected to a 55 gallon reservoir.

Every single run my plants always look super healthy and green while vegging on a 4x8 tray. Then a week or 2 into flowering the yellowing starts. My pH is around 5.7-6.1. Humidity is 50 and temp is 78. Nutrients is 1 part CNS17 bloom from Bontainicare. I have my watering timer on for 15 minutes twice a day. 1 hour after lights on and 2 hours before lights off. Medium is 4" Rockwool cube and hydroton

What could possibly be causing it to yellow / droop now that I'm using a one part?

Also... I have a 2x4 flood tray with 8 smaller plants in 4" rockwool. They've all been flowering the same amount of time in the same room but they don't have a yellow leaf or any drooping at all. Could my problem be the hydroton?

Anyone?

They getting enough oxygen?

mmjmon said:

They getting enough oxygen?

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The roots ?

NemoClones said:

The roots ?

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Yes. The water the roots are getting.

mmjmon said:

Yes. The water the roots are getting.

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The buckets only fill up for 15 minutes then drain out. I don't think it's possible to give them oxygen while the buckets are flooding.

What ppm are you feeding? Looks like a nitrogen def as the yellowing is on lower leaves. Could be lockout tho, need to know ppm and are u giving feed everytime? Also is this dtw or recirc?

westcoast420 said:

What ppm are you feeding? Looks like a nitrogen def as the yellowing is on lower leaves. Could be lockout tho, need to know ppm and are u giving feed everytime? Also is this dtw or recirc?

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This is recirc. Im getting a ppm meter when I get back on Monday. I never kept track of ppm. Probably my problem.

This may be my problem .
Is this salt or from the hydroton?
I change my water once a week.

Drain resi..
put in fresh ph water...
Flood and drain the buckets in 15 minute Increments for 1 hour.....
Drain that water.....
Do it again with fresh ph water...
Then add my nutrients and pH.....