SnS,
I'd love to see you give hydro a try. I know you wouldn't be disappointed. My advice would be to just do something small and simple at first to check stuff out and get the hang of it.

Stinky,
Most people don't realize how dangerous guano is. Since there are so many safe alternatives I don't even consider using it due to the health risks. Anyone handling it should have a full hood respirator. Don't look at it, and don't breath while near it. Research this shit if you don't believe me.

veggi,
I know my perlite changes color after a few feedings, it gets brown. Maybe a nute soak?