Quote Originally Posted by criom

im going to be using about 18 feet of ducting all together
That's a fairly long run, particularly if you're using flexible duct.

Axial blowers can't push into a lot of static pressure (backpressure). Air pressure leaks backward between the fan blades. Axials won't meet their CFM ratings if there's a lot of flow resistance/backpressure downline. Example of an axial fan.

Centrifugal types are better when you have to push air down a long run, through a few 90 bends or through a carbon filter. Example of a centrifugal blower.

I'm probably not giving you any good news as centrifs tend to be more expensive than axials. Sorry!

If you can shorten your duct run or replace long straight sections with plain steel duct, it'll move more air.