Good info here. Everyone says to learn to read your plants and give them what they need. Can someone go a little deeper on this for me? For example, if my leaves start turning yellow on week 4 of flowering, I think they need more N...where do I get more N? If I'm using FF, should I add more grow big? If I'm using biobizz do I add more bio-grow or top max. Super soil do I top dress. Won't even as about AN. Just wondering and thanks!