medicinal

@Bigdjm88, Rinsing out Coco with plain water is not a good idea, it messes up coco's Cation Exchange Capacity. Well at this point, if the growth has stopped then there is not much to lose. If I were you I would either transplant into soil and keep using Biobizz(it works wonders in soil) or I would get Coco specific mineral nutrients.

Does the substrate have any organic matter or is it just coco coir? BioBizz nutrients like grow, bloom etc need microbial life(which coco coir doesn't have) in order to be broken down. Otherwise the nutrients won't get absorbed by the plant. I too made the exact same mistake of using BioBizz Grow and Heaven in pure coco coir and had extremely slow growth with nitrogen deficiency in the lower leaves.