Ventilation in Reef Room

[gregzz4]

I'd look into a proper fan ... maybe around 10-15" and 120VAC, and some appropriate intake ventillation to accomodate the rated airflow of the fan, plus about 20-30%.
Something such as below. You could use a timer or whatever. And the intake louvers will keep cold air out in the winter if you get active ones, plus louvers on the intake side.
Keep in mind the louvers need to be sized correctly and purchased separately

https://continentalfan.com/wp-conten...t_Fans_PEF.jpg