Can I use an aquarium heater in a reptile terrarium?

  I have a 100watt submersible visi-therm stealth aquarium heater, can I use it to heat the terrarium if it's not underwater? If so, where is the best place to put it?



For reference,

terrarium-20gal AGA

livestock-2xBufo alvarius



current heating-zoo-med heating pad (not putting out enough)



substrate-repti-bark
Is not a good idea, those heater are designed only for underwater use. Try to put the terrarium in a place in which your animals (toads I supose) can recieve sunrays at least for a couple of hours every day.
nah, they are designed to work under water and will malfunction/burn out if not submerged under water ... depending on which animal you got you will need a uva & uvb lights that emiit heat and help your reptillian friends produce vitamin d & k from the rays .. which aid bone health (himans and reptiles are similar in the fact that we have trouble producing vit d, k and calicum .. so make sure your dusting the crickets with a calicum and vit d supplement).
nope there designed to be used only under water and not safe if there not submerged pets question and answers,www.5d2d.com

you may have to invest in a heat lamp the uv it emits is also good for them