CFM Needed?Help please

Hi

cfm needed for 25 cubic foot room?

buying a 4inch inline filter to push 135cfm

is that overkill?

Hydroponics KIT 63W 4" FAN Blower Carbon Filter 4" X 10" 2XFAN Ventilation Duct

for

Hydroponics 400W HPS MH Ballast Cooltube Light KIT Grow Tent