Gee, what a workup... Such a long discussion when the major problems are obvious. The biggest problem is the enclosure - ESPECIALLY the open top. Glass is a poor holder of heat, and that, combined with the open mesh top which allows all your heat to just rise out of the enclosure by convection, makes it almost impossible to heat sufficiently, and especially for an Antaresia, which are not frequent climbers and will spend most of their time on the ground. You have been given some very bad advice on the needs of your animal, and what you needed to ensure it remains comfortable. As PP has said, heat rocks are not good for snakes (they're not good for anything really), and ceramic heaters don't project heat the way a heat lamp does, they radiate it, so they need to be inside the enclosure, and the enclosure needs to be covered so the heat does not escape (nothing flammable of course...).
I'm guessing you've spent a lot of money setting this up, when a 25W heat cord placed under the tank at one end would be the cheapest, most effective and safest way to provide heat for your animal, and the belly heat would especially suit any Antaresia. A 25W heat cord zig-zagged (and not touching itself) to cover an area of about 35cm or 40cm square will provide sufficient very gentle heat, and a gradient from warm to cool, so that you might not even need a thermostat in winter - you would need it for safety in summer though. You need to place your thermostat probe on the floor above the heat cord so that it controls the temperature of the floor, not the surrounding air, and set it so that the floor in that spot reaches 32 or 33 degrees C. Heat cords are cheap, very safe, and waterproof. I have used nothing else in over 15 years now with everything from Antaresias to GTPs (I make my own heat panels with them), and never had one fail or let me down. I'd sooner pay to run a 25W heat source than a combination that can run into hundreds of watts per hour. if you are using lights to produce heat, you are wasting a lot of money.
It really disappoints me to see what new keepers are told and sold when setting their first animals up, and to be honest some of the advice in this thread is dodgey as well. There is usually a simple and cheap solution to most of these problems, but I guess outlets have a vested interest in selling as much junk as they can to increase their profits. It's not unusual to hear of someone spending $1000 on gear to keep a $100 snake. Crazy and dishonest.
Jamie
