Nitrogen deficiency possibly ?

went to see my girls today all looking good got 15 gorilla bomb and two unknown strains that were started a few weeks ahead anyway one of my girls lower leaves are yellowing and crisping up at the ends not sure if I’ve over fed or under or something else is happening need some help, cheers btw growing in biobizz all mix and biobizz grow as I am in veg have gave some root juice also after transplant

You'll have to present more of the details of your grow, otherwise, it's going to be hard to say why one or two leaves did this or that. I will say just through observation that your plant's leaf tips are clawed down, which is her way of telling you she doesn't like something. Whether it's a N deficiency or toxicity or something else all together is another story. You'll need to factor in variables such as what makes up your biobizz, what nutrients does it contain or not. What does the biobizz grow contain, in terms of nutrients? Are you getting all your micros in this mix as well? How much are you feeding? Do you pH your feed; if so, at what pH? Lots to consider my friend in order to get any sort of helpful advice. I will say this; two or three leaves does not a grow make. Take your time and do your homework; you'll be fine.