Looking very good man you must be doing something right lol. 82 is a little high on the temp side but with such a low humidity level I think you'll be fine since your risk of mold will be much lower. There are ways to raise the humidity but I'd say if your system isn't causing any problems, don't mess with it. As far as nutrients, whenever you do need them I'd check out the General Hydroponics or the Earth Juice lines. They're both organic and are widely respected products. I'm also a new grower and I found that buying a book or 2 on growing cannabis really gave me a strong base of knowledge on the subject, Jorge Cervantes has several how-to books. Hope this helps bro