Help with Asian bull frog! Heat mat vs. heat cables??

[ricky]

Hello there

My wife returned from Thailand with a tiny asian bullfrog in the suitcase She didnt know!! See pic below

We decided to keep the little buddy, but i dont have any experience with frogs - only snakes many years ago.

Therefore i seek a little help.

Im making a new vivarium for the "chubby frog".
The frog lives on the forest floor and likes to dick, so and I want to give him a solid layer of soil.

I plan to use a layer of Leca stone first and then a thick (appr. 5 cm) layer of soil mixed with coconut humus.

Now, how would it be best to heat the vivarium? Its 45 x 45 x 45 cm.

If i place a heat mat under the vivarium I assume the soil will absorb most of the heat??
Should i place a heat mat on the side? or simply go for heating bulbs?

I live in Denmark, so it gets cold in the winter time.
Lowest temp in the room would be 17-18 degree celcius.

Any advice would be highly appreciated!

Thanks

Best regards

Ricky