First off, hello Allan! Thanks for taking the time to fill out the relevant questions!

Quote Originally Posted by Treozen View Post
Everything here makes sense, and at the same time, conflicts with other sources. Which sources are right? I've read you must have 2 inches of substrate and the probe is on the glass-side so as to get an accurate reading. Its very confusing when the guidance is so contradictory. ;-) I've even seen tanks with 4 inches of ground cover. I wonder if the snakes get together and compare substrate depths - like humans might cars, or shoes.
The reason the thermostat's probe goes OUTSIDE of the vivarium is because if the snake urinates on it, water is spilled on it, or it is moved, it will register a cooler temperature which can cause the thermostat to spike to compensate, ultimately leading to fried snake when the temperature increases too much. If you search on the forum here you can read all about why thermostat probe placement is incredibly important!

Here's a good visualization for you for the probe placement:



In regards to humidity, that is definitely too high. I personally use a combination of a UTH and a CHE for my ball which keeps her humidity perfectly in check! Something to note here though is I live in a very humid area so it is a battle for me to lower my humidity.

About the substrate depth - what bcr229 means is over the UTH the substrate should be very ​shallow to allow heat transfer. The other parts of the vivarium are able to have thicker substrate.

Another note- you say you have Eco-Earth coconut fiber substrate. Was this one of the condensed bricks you needed to add water to? If it was that would also hugely raise your humidity if you only have a UTH on your vivarium.

What kind of thermostat(s) did you order?

Would you mind sharing a picture of your viv for reference? A tank that big would need a lot of clutter for a baby ball python to actually feel secure in, and it would help with suggestions to better prepare you for your BP!