If you have a mold problem in your basement.. you may want to consider running a sealed room (NO in/out for the room itself).. A 12000 BTU portable A/C with direct in/out ducting would be perfect for the size of room you are running if you have your light in a sealed cool tube loop (Or.. if you go LED.. which I HIGHLY recommend!). The A/C acts as a dehumidifier as well.. and by sealing the room.. you also make much better use of your Co2 becuase your exhause wont be sucking the Co2 out once an hour or w/e. Sealed rooms are a little more expensive to set up.. but being able to seal off your room from outside elements and control every aspect of your room is priceless imo.. Good luck!