Purple Kush growth issues

[seedinglife]

Hey there,

Im in week 3 flower with these girls and are having growth issues,
they are yellowing out a little and have a curl, (hopefully the photos show it clearly!)

Room is 9PM- 9AM gets night time temps of 26c and lights on of 30c
I found the rock wool base was tending to be too dry so increased watering cycle to x2 per light cycle vs 1.

Each 4 plants are under a 600Watt HPS with 700mm of clearance, and lights are in cool-tubes.

I have reduced the nutrient strength to 6-8 EC being:
Plantastic Bloom - 1/4 strength
FU63 Root repair - Normal doesage
Go Green - for repair/bring back vigour
Defuse - sterilising agent

Looking into deficiencies that could be causing it are sulfur or zinc in balance. explaining the twist and discolouration.

Have just done the new tank for the week and changed the water cycles so will post update tomorrow of hopeful improvement.

 

[SMALLTUBES]

hey there i am growing purple afghan kush and they look like yours..im not having yellowing...but they looked like they have stretched out and topped off...my are super small from clone....so they need a longer veg time......i use gh 3 part formula in pro mix no checkin ppm or anything...

 

[seedinglife]

Had a swing in PH from 5.8 to 8.
One row had a water lock, which i elevated to help run back to the tank, it was suggested the balls could be an issue...

Im pulling 1/2 a bucket of balls and putting them into 5.8PH water to see if they are rising the PH.