I'd start with the thermostat at 80 and see how warm the heater gets. Depending on where the temp probe is located you may need to adjust the thermostat to get the right value.
You can also put a brick on the habitat heater for about an hour or so once you've got the heat set to test it out - then you can measure how warm the brick is after having been on the heater for that long, to give you an idea of how much heat the tortoise will be getting.
You can also put a brick on the habitat heater for about an hour or so once you've got the heat set to test it out - then you can measure how warm the brick is after having been on the heater for that long, to give you an idea of how much heat the tortoise will be getting.
