I am in the process of settings up a terrarium to house tree frogs. I have buried a heat cable 10cm deep in the coir substrate as one of the tank heating methods.
I had the thermostat set to 25°C with the probe just above the surface of the coir.
Unfortunately this was a hard lesson to learn, the substrate temp reached almost 50°C and killed my Monstera Deliciosa. The roots seems to have completely disintegrated. Other plants seem okay for now, I have some ivy and ground cover type plant.
I have now buried the probe to get a better reading on the substrate temp, and turned the thermostat down to 19°C.
My question is, what is ideal substrate temps? I can’t seem to find much info using google... Obviously 50°C was waaay to high.