Skinny leaves in pre flower day36

[Beydot98]

Growing some gorilla cookies by fastbuds in coco and shes had issues throughout the grow unlike the forbidden runtz next to her. Currently feeding 1L at 5.8-6 ph per day. Since shes started pre flowering the top leaves have been coming out skinny. I lowered the water intake incase it was overwatering but after 4 days still the same. Ive been giving half the recommended nutes using the canna range.
Any suggestions as to what it might be ive hit a blank.

 

[St. Tom]

Growing some gorilla cookies by fastbuds in coco and shes had issues throughout the grow unlike the forbidden runtz next to her. Currently feeding 1L at 5.8-6 ph per day. Since shes started pre flowering the top leaves have been coming out skinny. I lowered the water intake incase it was overwatering but after 4 days still the same. Ive been giving half the recommended nutes using the canna range.
Any suggestions as to what it might be ive hit a blank.View attachment 1562183

I think she either looks very hungry or lockout with salt build up as with coco if your top feeding it should be to run off otherwise you will get problems .also skinny leaves are just genetics thin leaves are more sativa and big fat ones indica if that's what you mean