Is this normal?

The lower leaves of my plants are turning yelllow and dying.... ive been giving a regular light dose of nutes for about every week and a half but still that doesnt seem to help. its not out of controll or anything and the rest of th eplant seems fine. Should i be concerned about it or is it usually normal for lower leaves to be kinda doo doo?

looks like a nutrient deficiency. are in vegging or flowering?

veg for 2 weeks. the fert i have is schultz 10-15-10

for veg, use a higher Nitogen content fertilizer (say 15-10-10) Nitrogen generally makes leaves greener.