The Lettuce 'Raft' Type System
Basically; cut out six holes in styrofoam or polystyrene and mount your 2 inch net pots. Lettuce seeds are planted in rockwool (or your preferred medium), put in the net pots and surrounded by hydroton. The whole 'raft' floats on the surface of the water, an air pump provides the necessary oxygen to the roots.
I'll be growing this with my 90 watt UFO LED light in the new grow room.
Weekly Pictures (Click to Enlarge)