insulation

I have a floodlight on my refugium below my tank that runs pretty hot. I recently installed a computer fan down there to help out but I was thinking of using those insulation foam sheets to put along the bottom glass to provide a bit of an extra barrier from the heat. My stand is one of those...

I was thinking to save energy to use a type of styrofoam to insulate my custom sump and refugium. My filtration is located in my garage where I see huge temp swings from summer to winter. In the winter I have a huge inline pond heater and in the summer I run a chiller. The room temperature is...