Rusty Sugar leaves ?

[Zeo 122]

Hey guys 

 

I’m growing some white diesel haze, I’ve got 2 of these going , one is a lot bigger than the other , I think this is due to me over watering the smaller one when it was young... any way I’ve noticed over the last couple of days I’ve started getting rusty looking sugar leaves on the bigger one. 
I don’t think it’s light intensity as the “smaller” one is actually taller and that ones fine.... any other ideas what it could be ? 
 

so info 

 

1x1x2m tent 

coco , hand watered 

Dutch pro auto flower nutes 2ml/L 

Dutch pro explode 1ml/L 

lights : Spider Farmer SF2000 (x2) on 18/6
pH is good 

ec 1.2-1.3

 

I’ve noticed it’s spreading across the plant, it started with the main kola now it’s on pretty much all of them. 
 

im on week 5 of flower with While Label Seeds saying they take 5-7 weeks , so I’m assuming it’ll take a little longer than what they say .

 

any advice , things to consider ? 

[Absurdist 1,631]

Have you checked for pests?

 

Whatever it is you'll be able to ride it out as there's not that long to go.