So I'm on Day 7 of my first time growing using DWC method. Everything seems to being going OK except I feel like she's growing a little slower than the norm and the first two fan leaves seem to be curling downward on the ends. I've read that this could be N-tox, too much lighting, and numerous others. My setup is 2x2x4 with a 200cfm exhaust fan leading to an external carbon filter, 300 watt LED panel which puts out roughly 140 watts I think, I have a 5 gallon bubbler bucket with hydroton, and started germination in a rockwool cube and have since put the cube in the hydroton. I keep the pH between 5.5 and 6.0 exactly, the humidity I keep between 50%-65% and temperature fluctuates between 68° to 79° from night to day. Today I removed the rockwool to check root growth on the bottom and it is growing straight down toward the res like I want but I'm seeing very slow growth on the top and the curved fan leaves. Any ideas what this could be? Anything I should change? This is my first time so I've tried to pay close attention to everything and do it the right way. Oh and I have yet to feed nutes because I've read you should wait until 2-3 weeks and the water I'm using is out of the tap which I let sit 24 hours to get rid of chlorine. Any advice would be great!