Help please: leaves all turning yellow

[DezmondG]

Hey everyone. All my leaves on one of my plants are turning yellow. Don’t know why?
organic soil
Tap water and remo bloom
600w HPS
Temp 24 Celsius lights on and down to 18 Celsius lights off
Humidity 40-50%
Day 33ish in flower.

 

[Herby Paisley]

...Could be lower nitrogen in that one plant causing her to yellow more or because your getting later in flowering she could be feeding off her reserves now that have been stored up in her fan leaves.

 

[DezmondG]

...Could be lower nitrogen in that one plant causing her to yellow more or because your getting later in flowering she could be feeding off her reserves now that have been stored up in her fan leaves.

Cool thanks. I just got a ppm meter and want to check out to make sure I am feeding them enough. Will be back with the results