1. I buy mine from Home Depot. As long as it is fiber glass it will work. The smaller the spaces in the weave the better.
2. Yes it will work. Land plants want around 6500k for photosynthesis. 7000k will be bright but shouldn't be to bright.
3. 1.5625 cu. ft. for 3" deep
4. You can paint the outside glass black to hide the drainage layer. Keep a section on the side of the tank open so you can easily tell when you need to siphon off excess water.