really, shitcan the foil, either paint the inside of the box flat white of leave the inside of the box nekid, the foil will cause hot spots that will stress the plant as it get's bigger.
also, either find a way to get that fan inside the box or get a smaller one that will fit, you don't want a fan blowing directly on the plant at all times, with a fan oscillating, it only blows on the plant part of the time, it sorta mimics the wind. what that will do for you is make the stems stronger.
as for feeding, i'd wait a week or 2 more and then start with a very weak concentration, maybe 20% of what the directions say to use, you don't want to use full strenth for a little baby
and Mikey, you have to start reading the FAQ's, first because you can be sure the answer you get is accurate, let's face it, some of the advice you get might come from people who know less than you do.
second, because the FAQ will give you the WHOLE answer, not just what i can remember
third, because reading the FAQ's will show in the kinds of questions you ask, and then people will see how willing you are to help yourself and they will become more willing to help you. not that they are unwilling even now but, if you want respect, you have to earn it.
anyway, hope i didn't offend you, that wasn't my intent. and don't stop posting and asking for help, just read the FAQ's so you can ask tougher questions

bozo,
peace, love, dope