A:AnswerAltho the fog, itself, has a noticeable smell - kinda sweet/musty, it's hard to discribe - it doesn't leave any residue.
The fog solution is water-based, so there may be some moisture or condensation near the nozzle.
FYI: If you're gonna use the Fogger indoors, be advised: it WILL set-off your smoke detector(s)!
A:AnswerHello
You need fog juice
Some lighter some heavier
Lasts according to how much u use it and size of reservoir
Remember u must clean it out after use not to gum up the works manuals give directions