Pale plant

Yes you gave all the answers yourself already. And I also know the reason for this Nitrogen lockout. Stop giving the Bio Grow nutrkent. It does contain too much Nitrogen for this phase of the grow. Flush the soil with 2 times the pot volume in water. Make sure that this water got the right pH and nutrients. You can add the nutrients that you gave before but cut the Bio Grow from now on. Let the soil dry till the top inch of the soil is completely dry. And continue feeding and watering like you did before but without the Bio Grow. Enjoy your grow!