Good luck with the grow mate... just one thing has your lights got reflectors on them? shine more light onto your plant im doing the same set up in my grow box have 2 x 125 watt equivalent.
In with your grow to mate :)
Im new to the growing and i was just wondering what is better to use, Hydroponic NFT System - Nutriculture Gro-Tank or Hydroponic Flood and Drain System - Nutriculture Flo Gro, Also will using clay pebbles in these alter anything?
the foil isnt a bad idea it is a good reflector but you might want to cover all the walls like i did, also as sunnyd said i would do it after about 4 weeks... what light are you using how many and what watt?