Yeah, if you're using only coco coir, even if you lay a thick layer, its still able to be manipulated to the point where the snake can come in contact with the floor of the enclosure. I use a mix of substrates and nestle the probe so its visible on the top but submerged in the substrate...I have my thermostat set way high because of it though, so Im always checking the probe to make sure it is in place, and making sure there is no displacement of substrate in the hide... if you're going from newspaper to coco tho, id say keep it thin and have the probe on the floor of the enclosure