1) Cover tank with thick blankets. Emergency blankets work well for holding in heat and are around $2.00 at Walmart.
2) Fill a thick bottle (shampoo bottles work but clean them out well) with hot water. The bottle will stay warm for about 3 hours. The larger the bottle the longer the water will stay warm. You can wrap a damp clothe around the bottle to help boost humidity. Insulate tank with a thick blanket to help trap in heat. Remember to keep an eye on humidity levels.
3) Place the tank in your car and keep the heat on for a bit. The heat won't need to be on the whole time the crabs are in there, just check periodically and turn it back on once you start to see the temperature of the tank decreasing.
4) If you have a smaller tank you can fill the bathtub with warm water- it doesn't need to be filled to the size of the tank, just enough to keep the bottom warm. The humidity will increase quite a bit. You will want to keep an eye on it and vent the tank lid.
5) If you have Eco Earth or another brand of coconut fiber, you can mix with with warm water and it will help keep the tank warm for a couple of hours or more.
I hope this helps and if anyone has any other ideas, feel free to add them to this thread
![Smile :)](./images/smilies/icon_smile.gif)