No a fan is needed for optimal growth in an indoor environment. As I said, it:

A) Circulates air, helping the stomata under the leaves respirate by simulating outdoor breezes and temp fluctuations.

B) Stresses the main stem by causing micro tears in the fibers of the stem. Just like human or animal bones, the small tears are repaired by localizing CALCIUM deposit on the tears to make them even stronger. In fact, did you know you almost CANNOT break the same bone in the same place twice? The repaired bone is stronger than the non broken bones.

This holds true even in plant stems.

C) Protects from heat. Stagnant heat is deadly to plants and in an indoor environment, it is even more dangerous. Fans keep the air circulating, allowing the heat to remove some moisture and continues to keep hot air from smothering the plants.

If you grow indoors, you MUST have a fan for optimal growth potential.

15 Sq. Ft. is what you have Upinsmoke.....you definately need a fan.

As for your dual chamber setup.........perfect idea...jsut work out the logisitics first.

here is kinda a crappy pic of mine cuz I cant reach back far enuff because of my work bench.