Just a couple of questions.

1) Do you have previous cannabis growing experience?
2) Where did you pick this method up?
3) Have you seen this method take a plant all the way to harvest?
4) What nutrients and additives are you using?

The light can kill all exposed roots, and it will cause algae to form inside. (not ideal). Plus, cannabis roots in soil need the fresh air that watering from the top provides. (via gravity and suction)

Will be real interested in watching your progress. :thumbsup:

Also, filling-out the troubleshooting form would help with a more accurate diagnosis, but you've gotten some sound advise so far.