Ok, I know a few of you have ventilation fans due to have either large tanks and/or enclosed fish rooms, and I was wondering what type of fans you have and how large they're rated for. I'm looking at the Panasonic whisper series fans, while more expensive than the ones you normally can get at the big box store I've read a lot of good reviews about them, and while I doubt the tank is going to be dead silent reducing one sound source as much as possible sounds like a good investment. So what sort of CFM rating should I look at? I'll have in the neighborhood of 500g worth of water volume. It'll be hooked to a humidistat so it doesn't run constantly (better not!). The entire tank is going to be enclosed, I'm not sure if actual cubic feet is relevant, but it'll be somewhere in the neighborhood of 320 cubic feet when you count all the enclosed area, however fish tanks/stand/etc will take up a sizeable percentage of that volume. Also there's a slight problem in that the fan can not be ceiling mounted, it needs to be wall mounted (long story, joists run the wrong way for me to be comfortable drilling a 4" hole though a bunch). Panasonic has a wall mount, but it's only for like 110CFM not sure if that's good enough or not. Not sure if I can mount a ceiling fan sideways into the wall or if orientation of the fan is critical to it's operation. I could always use an inline fan as well too as they have some that are rated for fairly large volumes, although they are a bit louder so I'm guessing not as efficient as one where the fan is next to the humidity source.