Turn the intake fans around so they are removing hot air from the room, preferably from the top and close to the light. You do not need an intake fan. Simply leave a hole/s slightly smaller than the exhaust for air to enter through, cover it with a flap of poly or cardboard box, or make a wooden or metal light trap so air can get in but light can't.
Air will flow in just as fast is it is being sucked out, making the intake slightly smaller creates a bit of negative pressure, and stops smells leaking out.
Also make sure the exhausted air is going somewhere, not just into the room your box is in, or you'll just be cycling the same hot air all the time.