This is how I keep my greenhouse warm at night and cool in the day. My lights run at night indoors. So I take all that heat and use insulated ductwork to run it through to my greenhouse. Once it gets to the greenhouse it goes through an insulated ductwork. That I have put holes in throughout. Right now it just has petunias. But pretty soon this area will be full and I will make a loop around the whole garden. It does a couple of things. Keeps the warm air flowing for free. Also keeps some of the massive condensation From getting to the point of dripping on plants. No drips no botrytis as far as I’ve seen! In the super hot days of summer in the high desert are use air conditioning indoors. So whenever it exhausts it gives the girls a little cool relief also. I don’t count on it for cooling. Just kind of a little extra. I live at 3200 feet. And we can have freezing nights in late June and late August sometimes. I end up heating The greenhouse until November. So it is actually a huge help as my heaters are on thermostats. It’s also just a nice little tickly breeze going up through the leaves. And I think they like it. And hey Scotty I have started the book slime. Quite interesting.