Alright check it. 400 hps is great for flowering. It should help u yield a great deal more than just cfls. Not sure what lights are in an aero garden but im pretty sure they r cfl.
Linning ur room with foil is a big mistake. Foil will increase the heat of the light and a hps light is already extremely hot. U need to get that out of there and put mylar. Mylar can be found at ur local art store or hydroponics store. White walla are also very reflective and would work just fine.
As for circulation, this is very important! U should have an oscilating fan to constantly circulate the air in different ways in the room. U dont want a fan directly pointing on the plants and not oscilating, it will freeze/burn the leaves.
U should order a water ph tester on line, not expensive. If the ph is off u plants wont digest nutrients from the water properly abd could cause blockages that will stunt the growth.
Also research the use of bat guano. Very good to mix with ur soil.