Sorry to hear about your dog man... I may get pummeled with rotten tomatoes but my dogs are my favorite pets.
Make sure that it either has a sliding (locking) top, or if you get one that just goes over the top of the tank, make sure you get some clips for it. I would definately add some greenery in there... your snake is probably around 15-18 inches.
You are probably thinking of a ceramic heat emitter.. it screws into a light socket basically and it emits heat. You will need to get a thermostat or a rheostat if it didnt come with one, to control the temperature. In that small of a tank if you dont use one, it's going to get over 100 degrees probably. An alternative would be to go down to Home Depot and get yourself a Lutron table lamp dimmer. These cost about $11 and work wonders. Good luck.
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-Chris
The reason mainstream thought is thought of as a stream is because it's so shallow. -George Carlin
A fool doesn't learn. A smart man learns from his mistakes. A wise man learns from the mistakes of others. Which one are you?
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N. American Rat/Corn snake care sheet I wrote
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Current snakes:
0.1 Licorice Stick Black Rat (Lola)
1.0 Black Rat (Frankie)
0.1 Texas Bairdi (Rosa)
0.1 Blue Beauty (Brunhilde)
1.0 Green Tree Python (Monty)