Firestorm clearly states you need to buy a decent digital thermometer to verify your temperatures. Thermostats are notoriously inaccurate. So much so that a lot of them even state as much in the instructions! Im very surprised your vet hasnt been through this with you!? Do you have a thermometer? I keep all my snakes with belly heat around 90- 91F and ambients of 78 - 82f. Works great for me, ive taken on a few non feeders, and some of them are now my best feeders! All mine eat frozen/thawed. I warm the rats in hot water for about 30 min - hour. I then dip the head in just boiled water for 10 seconds. If the snake is showing interest but not striking after 40 seconds or so ill reheat the rats head in boiling water again. most of the time this works. If not i usually have a day old chick on hand to scent the rat with. This rarely fails!