whats up??

You can get black hose cheap at petco. The clear acts almost like a fiber optic cable... bringing in the light to your res. That slime on it is probably from the light.

PH 6.5 is a bit high for hydro. Its perfect for soil. Try aiming for 5.8...

All that yellowing was definitely from lack of nutes. My hydro girls always want nutes much younger than soil because the lack of nutes in plain water compared to dirt. I will use 1/4 str nute solution when they are small and watch how they react.

Theres also no need to cut off those yellow leaves. They are yellow because the plant is using up all the energy stored in them. When you cut them off its basically a waste. When the plant is done with them it will fall off.

Well I hope I could help!
Good luck with the grow!