I see you've gotten some good advice regarding an exhaust fan. Something important to remember is thar you're going to want fresh air coming in as well. Keeping some kind of passive intake, being either ducting in or having something open to let air in (mesh windows, one of your openings, etc) is going to let cool air in as well. Make sure the room your tent is in stays a cool, stable temperature and that should help your tent stay cooler as well. Not sure what your running in terms of lighting schedules, but 20/4 is going to keep your tent cooler than 24/0, and 18/6 will keep it cooler than 20/4.