If you fill-out the troubleshooting form, I'm sure we can help better. Just by looking at them...it looks like insufficient lighting, possible rootbound, hungry, and and probable ph issues. (a fairly distinctive color of the leaves, and slight canoeing)

If that's all the light they get, I'd recommend some compact fluorescent bulbs to suppliment.
Water ph should be between 6.3 and 6.8 for optimal growth in soil.
Miracle Grow soil eventually runs out of it's nutes. How long have they been in the same pot? How soon till their next transplant?
What are you feeding them?
Automatic watering can keep the roots too damp. In soil, cannabis needs a wet-dry cycle, or you risk root rot. :thumbsup:

Anyway, fill-out the troubleshooting form, as this is the best you are likely to get, without further information. :thumbsup: