hey guys have just switched to 12/12 and lights from cfl to hps and put a net over. the tops of plant have been drooping then bouncing back one bloke said fungus gnats are the cause but if root system was fucked how could they bounce back and forth. anyone know what could be like heat or not airated enough. under watered.. pls note that its just the top layer of plants drooping badly under the net seems almost normal. ill show pic of them at there worst.. any help appreciated.