My Leaves Are Turning Yellow On My Budding Plant

My leaves are turning yellow I dont know why I started using nothing but water a couple of weeks ago and now there turning yellow. Im going into the 6week of flowering and this is a auto-flowering hercules 7dwarft plant. Any help would be greatly appericated thanks.

I am a first time grower so not really sure.. but what i will say is i think its normal for the leaves to die as it is flowering, my blue cheese is on week 7 and i noticed some of the bigger fan leaves dying around 4 weeks into flowering, hope this helps

this happens.

the plant has moved all focus onto the buds. the leaves wil dry and wilt, you can try using some veg nutes 1/4th strength, while still doing your bloom nutes at whatever strength you are. but its not a big deal. the plant is budding, and that means the end of its life cycle. it has stopped caring about the fan leaves.