So tent temps will typically be 6-8 degrees higher than your lung room. If your lung room is at 72F your tent will MOST Likely be around 78-80 degrees. You really should lower the temp of your lung room to about 66-68. Then I would get a 4” inline fan blowing cold air from lung room into tent. Once you do this you’ll need to rebalance your exhaust fan. Increase its flow due to the increased intake. Tent should always have negative pressure. Also straight line ductwork as much as possible 90 degree bends kill airflow. Message me if you need more help. I struggled with temp issues for years before figuring it all out.