Welcome To The WaterFarm Club Brother Daveroller.I Myself Have 3 Different Fans I Run.
1st Is The Super Quite TD Silent-150.With This Fan You Have To Supply Your Own Power Cord.Basicly Brother This Is A High End Fart Fan And I Have Had Both My Running For 3 Years And The Only Problem Ive Had So Far Is Carbon Dust From My Phresh Filter Got Into My Fan Bearins.I Just Blew It Out And She Keeps On Ticking.This Fan Will Run Ya About 225.00 TTD
2nd Is The Very Very Quite Vortex S Line Fan.This Fan Was Modeled After The TD Silent Line And The Reason I Belive It To Be A Tad Louder Than The TD Silent Is Because Its Shorter And Skinnier But Not A Deal Breaker.This Fan Will Run Ya About 200.00 TTD
3rd Is The Quite CanFan MaxFan.This Fan Comes With A Speed Control(Very Kewl) And If The 4 Inch Fan That Brother Puff Has His Eye On Doesnt Meet My Requirements This Is The Fan Im Going To Replace My TD-Silents With In My 2x4.The Reason Is Simple Brother,By Hooking This Fan Directly Up To The GreenGator Filter I Would Elemenate 15 Feet Of Ducting And Get This,This Combo Will Still be Shorter Than My 6x24 Filter.Here's A Link Below
http://growershouse.com/can-fan-max-fan-6-334-cfm