I hope I'm addressing this right,

I have a two story house and it's a real problem pumping cold air to the second floor and retaining it there. The cold air of course wants to sink back to the first floor and into the basement. At night the thermostat that is on the first floor, is satisfied being at 75 degrees and doesn't call for the AC to kick in. Second floor = too warm, first floor=perfect, basement=cold enough to hang meat. Any ideas?

Thanks waldig