Using Heat Mats for nano tanks

[ale36]

i have read a number of journals where people are using heat mats under their nano tanks and i have a few Questions:

1. What is the reason for using the heat mats?
2. Are the mats used instead of a submersible/in-line heater?
3. How do you control the temperature? i know there are heat mats thermostats is this what people use?

 

[Richard Dowling]

As far as I know heat mats are used for dry starts to keep the humidity in the tank whilst the plants spread, but personally I found that all the plants above the mat died out, the heat wasnt enough to keep them humid and I would have been better off just filling the tank and using a normal heater. You cant adjust the heat, its set to a certain level for reptiles.