that's a nice setup...those seedlings have still yet to really start growing...couple more days and once another set of leaves or two grow, they should take off..do look a bit stretched..get them closer to the fluoros if you can

Whoa whoa..just actually read it..3 weeks? they need some more lights or something...they don't seem to be growing too fast..

get some cfl's or something...how many tubes are in there? not near enough lumens to keep those young ones happy