Help 1st grow yellow leaves

[Carcar]

Help again guys it’s the first grow we’re getting close it’s week8 day 1 and i’m concerned about the yellow I know this happens close to harvest but I think I still have 3 weeks till a month left on some of these plants what do y’all think should I worry or nah

 

[Oldguy71]

Feed them

 

[ShrederTHC]

Is this coco coir with perlite?

Anyway looks like they need a higher dose of nutrients. if it's coco coir, up the watering volume as well.