CFL light doesn't penetrate as deep into the canopy. as HID lighting does. As someone stated earlier your setup would be more beneficial with the cfl's being around the plant, with a few above the plant. Your setup at the moment would work much better as a sog grow. Also as someone else has mentioned there's a large debate whether adding more lights actually increases lumens. Some say no matter how many cfl's you add your lumens would be equal to the lumens of your brightest bulb while others say lumens add up. Your best bet for maximum yield would be tt place the lights all around the plant.What do you mean by light penetration problem? All help and advice is wanted.