I am trying to reduce my tank temperature to 78. One problem I seem to be having is getting it down. The ambient room temp is 72. I raised the lids last night and left the ceiling fan on, I cut off the tidal off because it has a pump that sits in the water, and heater was unplugged. The temp of tank decreased from 82.4 to 81.4. The shades stay closed in the room where the tank sits and the window in the room faces is the side of my neighbor's house, so there is no blazing sun hitting the room. Do you have any suggestions to get the tank to 78?