If i use a 435cfm valueline fan for my grow room exhaust and my carbon filter will a 8" 250 cfm DUCT BOOSTER cool a 600w hps in a cool tube or should I just hook the cool tube up and exhaust, filter, and cool my light with the same 435cfm valueline?
You should hook it all up to the valueline. I dont think a duct booster fan will cool a 600 watt. At least i would not trust it to.