Sorry for the late reply. For future reference if you are in an emergency and need to heat the tank up, the quickest safe thing to do is to get some type of clean, sealed bottle, fill it with hot water, and float it in the tank. This way you won't be introducing new water into the tank, and it will help heat the tank slowly. You need to judge the bottle(s) and sizes based on your tank, and should have thermometer in the tank to monitor what's going on.
On the flipside, here in FL, in places where people keep the room up to temp for tropical fish &/or reptiles, and also have goldfish (usually as feeders), they take water bottles and put them in the freezer, and then float the bottles in the tank and rotate them out.
