Quote Originally Posted by Buzkill
A: have the odor control be my lights cooling air, filter then a fan, then light, then the last fan and out?
B: or must I use two separate air systems for both?
What is the CFM rating for each fan?

I don't think A is going to work. That just sounds odd. You may be able to do filter > light > light > Fan > Out.

If it were me I'd run closed system for the lights: In > light > light > Fan > Out. And a separate odor system: Filter > Fan > Out. Note that under this configuration you must ensure that the duct servicing the lights is air tight. Otherwise you will end up pulling odor through the lights and out.