Oh you guys and your METERS lol... blah. hahaha!
chzrh; are you planning on use a carbon scrubber at all? That second option is 176 CFM if this cubic meter per hour to cubic feet per minute calculator is working correctly. It looks like you can add on about a 4" carbon scrubber. If you went with the kit; I'm not sure if that fan is even powerful enough to properly pull from the scrubber. I think it
would work, but at reduced efficiency and you'd be working the crap out of that fan.
I'm using a 400 CFM fan to exhaust my 6" scrubber; most 4" scrubbers I've seen are usually rated around 200 CFM. Remember, the CFM (or in your case, the cubic meter per hour) is going to be reduced when you add resistance to it (via the scrubber.)
Also, price wise, 127 euros seems VERY expensive (at least converted to USD for my comparison) for that fan strength and carbon scrubber. You could get much more powerful fan with a fan speed controller AND a better scrubber for less than the cost of this kit. If it were my wallet, I would shop around a little and compare.
You can get by with passive air intakes; you will most definitely have some negative air pressure space in your tent with using just an exhaust fan; but ultimately I think you'll find you'll want an intake system down the road.
So if it were ME, I would ask myself if I'm preparing for the long term or if I'm buying this to see if it helps remedy a current situation. If you get a larger rated fan (more cubic meter per hour,) you could get a fan controller to slow down the speeds if need be or speed them up if temps start rising, you'd be working the fan less (less heat, longer life,) increasing the efficiency of the carbon scrubber (if the air flow suck is not strong enough; it won't pull the odor causing molecules to the filter, which could in turn instead find their way out your passive air intakes.) If you don't plan on expanding down the road; go with a more appropriate size/rated fan and scrubber.
That's just my two cents
