Hello Bob
Imo you should'nt feed her before 2 weeks as ur medium already contain food.
> never feed seedlings unless your medium is nute's free, as u shouldn't feed just after a transplant.
Fishmix is stronger than biogrow, use it with parsimony (cut the shedule dose by 2 or 3 first,see what happen, adjust..)
My 2 cents