Would you say your plants are in 16oz cups? My two females have been in 16oz cups since sprout (strain unknown), and now about 5-6 weeks later one is about 16 inches tall, and the other is about 9 inches. Besides some underwatering stress a couple weeks ago, They have been 100% healthy. I'm already flowering them because they developed preflowers about a week ago while still on the 16/8 light cycle... Im not sure if this is too early but I said screw it. I'm kinda just experimenting right now anyway.

In case you're wondering what my setup is:
-One 19 watt energy efficient fluorescent bulb
-MiracleGro standard potting soil
-Fed with MicracleGro all-purpose plant food once a week with a low concentration solution
-Watered generously approx. every other day.

I also cut a hole in the bucket and put a small fan in to get circulation in the bucket. The bucket also has white walls, which probably acted quite well as a reflector.

Now that I have it in flowering, Im putting a blanket over the whole thing to keep any light out during the 12 hour dark cycle and have a really ghetto fan set up to get air inside. I'll let you know how it goes.

Look at it!