The repti-foggers are AWESOME!. But......a little overkill for most tanks, even for a 40 or 50 gallon on the LOWEST setting. So I have mine on timers. ( On 1 hour - Off 3 hours ) 24 hours a day. $60 for the fogger & $20 for an LCD screen timer from The Home Depot. Plus, you are only suppose to run Distilled water in them to keep them from getting deposit build up. Lastly, they will drop your temps by 5-7 degrees or so when they cut on.

So they are expensive to start a setup with, and to run (buying distilled water for them) But... you never have to worry about humidity.

It's just about whatever you want to do.