The leaves are browning all over(especially near the bottom) and not looking to have much growth. At 3 1/2 weeks it looks a bit small and I havent seen any new growth for some time now. At 3 weeks I started nutes at about 1/3 strength. This morning I flushed it with tap water cuz I didnt know what else to do. I have it under 400w. I dont think the light was burning it but I still moved it further away (about 3 ft) The stem is very thick and sturdy. What is goin on???