I have a friend who wants to put in a aquaponic system in a greenhouse. He is surrounded by fields that are sprayed from the air. So I was wondering if a greenhouse can be sealed and what would be needed (to control temp. and the co2 level or anything else.) I have thought of misting and swamp cooler but I would imagine the humidity level would get off the charts. Air conditioning would be very expensive.
You're friend is in kind of a situation. I would suggest building vent chimneys on both sides of the roof. Therefore, when the farm is spraying on one side, you may close the vents on this side and open the ones on the other.
That would be good for spraying from a tractor but they are spraying from a airplane so it covers the whole building.
How surrounded by fields is he? 10' away? 50'? 500'?
50' on 2 sides & 100' on the other 2
I'd say go have a talk with the owner of the fields, but my guess is that would end badly.
The easiest solution might be to put a registered hive of bees in the greenhouse as well. The pesticide applicator would be obligated by law to notify the beekeeper before spraying and that would give you time to close up the greenhouse for a couple hours.