having 3 heat mats is not really ideal and linked to one thermostat not such a good idea. the thermostat probe would need to be next to the glass to make sure the glass does not get too hot, if one mat would fail then the glass of one side (where the thermostat probe is not at) could go extremely hot and possibly burn the frog if it were to lean on the glass. there also might be a risk of the glass cracking if sprayed directly because of the change in temperature but this has never happened to me but i personally wouldn't risk it on my exo terra tank. naturally, heat comes from the sun and therefore downwards so most animals will be used to that.