Two terrariums

[travelfin]

Hi
I am posting for the first time here. I have two terrariums with orchids.

And

Hope I did the right way.
But have about 100 orchids in them. Trying to solve the growing problems especially how often to recirculate the air. have fans running 24/7 changing the air quite fast and having the humidity too low. Or would it be better to circulate the air inside and have a higher humidity.
Willtry and answer your questions