Glass also eats light.... Taking away from the rated lumen output of the bulb.Cool tubes are great if you have limited space.Still you should have some type of ventilation other than the one you would use with the tube.You have to replenish the air,not just fan it around.Just a few things to ponder on.A 265 cfm fan would work with the tube.You should go with the 465 and a wye inline with flex.Good luck with ya grow!

Ga Grown!:thumbsup: