When did u start adding nutrients to your miricle grow soil? and how much? It seems like everytime I put my plants in the tent underneath the 400 watt MH like 4 days after the tops start turning yellow and the new growth between the nodes do.Don't add dolomite lime to it. Use hydrated lime (its water soluble) Use the dolomite when you mix up your soil *before* planting/transplanting. Test the run off of the mix and dial it in before planting. Let it dry out before testing again too.
The light green is odd. (for MG) If you look at it, the new growth has the 'meat' of the leaf being light in color. Go down a level or two and the meat is fine, but main veins are yellow. I'd say watch the pH of the water (and the pH of the first bit of run off) and see what happens.