I would go with a Vortex 449 CFM fan I think that is the CFM and about a 25LB carbon scrubber. I use that with 2 1K's going, and different smelly strains and works fine, I vent out side along with that.
I alternate back and forth with another oder nutraliser, but mainly keep that for the rest of the house outside of the grow room, but even when it is not going, the scrubber takes care of the smell. I have also used a Vortex 279 CFM I think it was and a 15 LB scrubber for a 1K grow in a 4x4 cab with good results.
Adieu