Initially I used 4 x 400mm / 16” fans, however I later upgraded these to larger and higher quality 450mm / 18” fans due to a miscalculation of airflow.
Can you share the calculation for the airflow of the room? I'm planning to do a familiar farm.
But mine will have some swamp coolers (since my area reaches outside ambient temperature of upto 48 deg Celsius in the summer).