what's your reason for wanting fog? if it's humidity, something like a mister would probably be more effective (if you don't plan on running the fogger continuously).
Otherwise, I'd avoid the in-tank versions, I've heard they can be damaging to the critters that manage to find their way to the ultrasonic bits.
check out dendroboards, they talk about this stuff a lot, I think there are a few DIY plans for converting an inexpensive home ultrasonic humidifier to a viv fogger.
|