1. Unless absolutely necessary get rid of the tent.
2. Put a floor box fan in the tent doorway. Have the fan .blow air .into the tent.
3. Pick up a couple little 6 inch fans for inside the tent. You can run them with the flap open.
4. If possible, keep the plants farther from the bulb. Gives less growth but less heat.
5. Bend the main colas so they are parallel to the floor so they'll be farther from the bulb.
6. Weather is getting cooler so factor that in to whatever remedy you try.
Remember that fans have 2 modes - suck and blow, and that heat rises. Fans on the floor should blow cooler air into the tent. Fans near the top of the tent should blow the hotter air out of the tent.
Good luck, BigSteve.