Solo zamnesia white widow

It is a N deficiency aka Nitrogen def as you have cut the nitrogen after week 7 and during week 7 you used compost tea instead of your classic organic grow nutrient. So you have 4 weeks without Nitrogen and you started straight with the bloom nutrients and the pk booster on the 1st weeks of flowering which is a pretty huge amount of PK compared to the amount of N you have brought. Knowing that cannabis needs Nitrogen until the end of pre flower , it means that you need to bring nitrogen during the 1st and second week of flowering ( but you can slowly decrease the amount ) before you cut it , if your plant is a 8 weeks flowering she'll be yellow by week 6 after 12/12 switch. Bring a little bit of Nitrogen to make it to the end of flowering but a light amount will help them to maintain.