nice looking setup, post some stats about it, couldnt tell what type of light that was but if it is HID your going to run into some heat issues, those type of hoods arent to good for small enclosures, i run a super sun 2 air cooled by sunlight supply and i hooked my exhaust up to it and i can actually stick my hand inside the hood enclosure and its not even hot inside,

also have you looked into mylar? you may run into hot spots with the aluminum foil i also found a report on another board where test were done with a light meter against mylar, aluminum foil, and white paint and beleive it or not your better off with white paint than aluminum foil, look up mylar on ebay you can get very cheap

not trien to pick you apart but beleive me its all love man, i dont wanna see ya make mistakes i have, its def no fun to veg a plant for 3 weeks to wake up to it bent over burnt to a crisp

also please post some dimension, do you just plan on growing one plant? you can def utilize more of that space you got