How Big of a Carbon filter?

I see this question all of the time. Never had an answer other than to WAG it.

Here is a link to a calculator that takes your room size, lights and gives a recommendation on filter size:

http://phreshfilter.com/selector.php



http://www.eastwesthydro.com/air/phresh®-filter-4x8-150-cfm-701000?utm_source=google&utm_medium=shopping&utm_campaign=product-feed