I have 2 large greenhouses. Yes you need fans, ventilation, misters and even an evaporative cooler in the summer if you plan on growing plants and keeping them alive.
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You've named every one of the helps I've seen in the commercial green houses I've seen in past years. I can still feel the chill on my skin just thinking of that lovely misty building.
I bought some of the misting hose some years ago for the dog yard. After a few years the calcium in our water clogged it up, which was a problem we had at the nursery. We have a LOT of calcium, among other things, in our water.
One thing my DH accidently found that caused some of his plants to grow faster, was to use blue glass on the top roof. A tree branch broke some glass on the greenhouse that held the very most expensive plants he had (of course!!) and since he was called in late at night, he searched around old storage buildings and found some glass a family member had stored "just in case he wanted to create a masterpiece of stained glass" and DH used them. Turns out in that part of the green house and that part only, the plants grew bigger and much thriftier. Very interesting I thought. I found it's called Color Therapy or something like that.