Mars hydro

Is your tent 24 inches x 24 inches or is it 2.4 meters by 2.4 meters? The best way is to use a vent fan with temperature and humidity control. That way the fan automatically does what is required to hold the temperature and humidity you want. I think the biggest openings in Mars tents at the top are 8" (20cm). You might be able to use one fan but it will have to run faster and noisier. If you want it to be quieter you might need two fans.

Work out the volume of your space...Length X Width X Height and then find a fan that will change ALL the air in the space at least twice per hour. Twice the volume per hr is the minimum ok. more is better as the more air you change over the more carbon the plants can take in and grow bigger with.