Phal bellina temperatures: don't wanna boil it!

[MateoinLosAngeles]

I have a Phal bellina x self seedling that is happily growing in S/H. The plant is growing next to other Phals on heat mats in a very small pot barely 3 inch above the mat. I have a sticky thermal tape that gives me an approx temperature reading.

I've observed that as December kicked in, this was reading too low for my liking. Reaching 60-65ºF at night, despite being on a heat mat. So I grabbed a smaller heat mat I had laying around and wrapped it around the pot like so:



Now, the problem is that I fear this mat might be too hot. The top of the pot where most of the roots are reads 85-100ºF. I inserted a household thermometer through one of the reservoir holes and the water read 95ºF.

I don't think this is very off from the temperatures in Borneo, but they feel a bit high. Here's an average monthly temperature in Kuching:



The heat mat is connected to a smart plug, so I can schedule it to be on and off and different times of day. The problem if I only turn it on at night is that the smaller heat mat heats the pot so much that it would lead to temperatures above 90ºF at night, whilst the plant would experience 75º-82ºF during the day. Making the plant be hotter at night sounds off to me.

The solution could be to time it so it's continually on except for the hottest times of day: between 10am and 4pm. But that would mean the plant would stay between 85ºF and 105ºF.

Am I gonna overheat this plant?!