Ventilation Help!

HEY EVERYONE I HAVE A QUESTION REGARDING VENTILATION. IVE GOT A 3.75 CUBIC FOOT SPACE TO GROW IN. I CANNOT CUT ANY HOLES IN IT DUE TO LIGHT POLUTION. I HAVE ONE AQUALIGHT FAN WHICH MOVES 31 CUBIC FEET PER MINUTE. MY CURRENT TEMPERATURE INSIDE IS RANGING BETWEEN 70 AND 80 F. IS THIS ADEQUATE? BELOW IS A PIK OF MY SET UP.
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