Those heating pads are not meant to warm a cage. All they do is provide belly warmth to aid in digestion only. Though the ceramic heaters are a bit on the pricy side, they last for years...at least for me. I use them for my lizard. I have an Australian frilled dragon. For the size tank you mentioned...a 25 watt should be good enough. If you feel the scorpion would be somewhere where it is cooler than the rest of the house, then perhaps a 40 watt. I always try to make it so that the animal can make it's own choice if it needs to cool off or heat up, by having the heating units on the opposite side of the water and have the water deep enough for the scorpion to stand in it, but shallow enough to where it doesn't drown. They do get the bulk of their water through their food. Speaking of food, do not over feed a scorpion. It can make their sides split (yuk). An adult in warm temps can eat one or two crickets a week. A juvenile, perhaps one cricket more per week. In cooler temps, they will eat less due to inactivity from the cooler temps. Their metabolisms slow down.
People who are afraid or eerie about these kinds of animals...scorpions, spiders, snakes, etc. are so due to the lack of knowledge on these critters. Find a DVD on scorpions. Teach her. Let her know there is nothing to be afraid of. They are safe and though rather boring as a pet, they are very incredible animals with incredible abilities. Maybe you can find a pregnant scorpion and maybe you two will be lucky enough, as I was to witness such a birth. Raising the babies is a challenge even to the professional, but gives a sharing moment of the one thing us females are all too familiar with
I remember my first Christmas out here. We were on the patio by the pool, swimming, BBQ-ing and on the phone with family back East laughing hysterically at our new experience of Christmas while they were shivering in their winter freeze. One winter here, a friend and his girlfriend went camping in Julian and they had snow up there at the time. They came back with the back of the truck loaded with snow and piled it in the front yard. We had ourselves an East coast style snowball fight!! It was great!!
Driving out here is suicide sometimes, but driving in Jersey can be just as bad or worse. You got tons of people back there in a smaller space. It's like taking half the population of California and sticking it in Rhoad Island...LOL. I drove 405 once into LA to see a relative that was out here on business. NEVER AGAIN!! if I can avoid it. That was the most stressing drive I ever made and that's when they were still doing all that construction to repair bridges and roads from the Northridge Earthquake. What a mess.