Looks to me like you have insufficient lighting. Get yourself a 4 tube fluorescent fixture and 2 each cool white and warm white bulbs, and hang them close to the plants.

Plant below is Lemon Skunk, 30 days from seed going into the dirt, 6 tube 4 foot T5 HO light, mixed cool/warm bulbs

Edit

Soil is a local potting mix with no added nutes, perlite added, and nutes are Fox Farm Grow big at half strength.. Clones (please let it be a girl!) will go into hempy buckets.