25mm fan + active charcoal filter + higher leveling feet

[IllDante]

I have a question, since the fan does not blow - rather, pull air into the system. What would be the purpose of installing a different fan? I toyed with the idea of re-fitting a 120cm fan to pull more air in at a slower speed thus removing a lot of the noise. But, are you actively changing the direction of the airflow? If so, why?