Sun leaves yellowing 2 weeks into flower.

[pokersmoke]

Hi, i'm 2 weeks into flowering all seemed well then I notice leaves on main stem yellowing added small grow nutrient 1 week ago.
But I am growing in plagron bat mix so nutrients shouldn't be needed?
Is this natural for fan leaves to do this as plant isnt in veg anymore?
Any advice appreciated.
thanks

 

[THE BROTHER'S GRUNT]

If it's just some of the lower fan leaves i wouldn't worry about it. Your plant will use the energy from those leaves for bud production if that makes since. It's early and sometimes i tend to ramble.

 

[pokersmoke]

yes that does make sense.thanks.
had a feeling they were more needed for vegging period.
I told myself at the start i wanted to keep as many leaves as poss but this always seems to happen.