Re: help with CHE
A Rheostat is more or less an electrical dimmer switch, the CHE was -always- be on, all the rheostat does is regulate how much power its getting. You're probably not feeling anything when its on low because the CHE is probably not getting enough power to even heat up, crank the Rheostat up to full and hold your hand over the CHE, I betcha you'll feel it getting warm after a few minutes.
The problem with a rheostat is the fact that room temperatures do not stay the same. Because it does not turn on and off and just regulates how much power goes to the CHE, the temperature of the cage will go up and down with the room. If the room is 70'F and the cage is 75'F with the CHE on it'll be fine. But if the room warms up to 75'F then the cage is going to warm up to 80'F. If the room gets hot and hits 80'F, the cage is going to be 85+'F.
The Thermostats can be hard to find locally, I think most people have to order theirs online. The Repti-Temp 500R or CA RF1000 Thermostat will turn the CHE on and off, so again if your room is 70'F and you have the thermostat at 75'F, if the room warms up to 75'F, the thermostat will turn off the CHE because the room is now at the set temperature. It will not turn on again until the room temperature drops below 75'F.
I mean I really hate to put down the lady at the pet store, but its starting to sound to me like she's just trying to make money off you, first suggesting the hedgehog food and that cat food isn't suppose to be fed to them (does she sell cat food?) and now a Rheostat over the Thermostat. If you don't want to order it online, I'm sure she can order it into the store next shipment day.
The main problem with temperatures going up and down is it can cause an URI if they're constantly going from hot to cold and back to hot. Same thing happens to humans, except we just get a common cold from it (trust me, I work at an ice factory, heh).