A carbon filter is a great investment. I sprung for a Phresh. She hasn't let me down running 24-7 since Nov of last year. Talk with your hydro store rep before purchasing to verify you have matched up the proper size to your specific system. CFMs are very important to the success of your odor control and exhaust system. You can PM me if you need a good source. I researched for several weeks and found some peeps I can trust.What is The best carbon filter i have 4x4x7 grow tent with a 6inch can fan. Im growing some sour d x trainwreck so its pretty stinky so i need one that will work dont mind paying a little more.