hetaing pads

Question
are heating pads dangerous? can u catch the aquarium on fire?

Answer
Most heating pads are alright if the species require warming from underneath and the substrate is non particulate,  I wouldn't use one if the substrate can be burrowed under like sand.  Most reptiles should always be heated from above, it is far more natural.  So I would not bother with an under tank heater, and go with a ceramic heat emitter with a rheostat.