Sorry, didn't mean to flame. I can only state what works in my environment. Ishould have mentioned that the fan is on a rheostat and though running 24/7 it's at about 1/2 speed which should add to the life of fan and filter.

The reason I say carbon is the ony way to go is because I've not needed to worry about smell for years with only an annual vacuum of the outside of filter.

Not To Worry: priceless