In the initial post I said I would keep them at 28'c-30'c, do not be alarmed! The aquarium is always at 24-25'c, fluctuations of 1'c may happen depending on the day. At the moment the tank is heated both internally and externally. I have the heating always set at 25'c both to keep warm and for the frogs (dart frogs) and the frogs. I have a internal heater in the aquarium just in case, equipped with a thermostat. And yes, I check the temperature at least 3 times a day, both with the internal thermometer and a laser thermometer (with the laser turned off).

One time my tank boiled (thermostat didn't turn itself off) and it ended up killing everything I had. I'm extra diligent to make sure that the same mistake does not happen.