Yup... a real fan is the way to go...
I use 600s.. and I had one in my tent... 20"x36"x54".. never an issue...
And remember, a 6" fan at half power will be quieter and use less juice than a 4" at full speed...:razz:
WORTH MENTION IS THAT YOU SHOULD NEVER A LIGHT DIMMER TO SLOW A FAN DOWN...