So I've heard that rheostats can be used with under tank heaters as well as heat lamps, and I know that thermostats can too, but what's the difference?

I found at my local pet store a 500R thermostat and also a 500W rheostat, but the thermostat was $52, while the rheostat was only $41.
It seems like these prices are a little far-fetched, no? And which one should I get anyways?
I need it for my corn snake in a 30gal tank where my Under Tank Heater doesn't seem to be doing the job without the lamp (which can't be on at night unless I get a night bulb)

Thermostats are controled automaticaly via a probe. You set a heat limit and it'll keep it there by turning the heating source on and off. This would work good with a Under Tank Heater but could be very anoying with a lamp.

Rheostats are pretty much just a dimmer which you control your self. You can just use a 10$ dimmer from lows for the lamp but you can't use them for the Under Tank Heater. You have to buy a reptile dimmer for that.

Hope that helped out a bit!

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Gerp, Gerp, Gerp.

I personally prefer the thermostats.
Just set them and check them from time to time and they do the rest.
Check online shops for them. They are MUCH cheaper than in the shops.

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Merlin,
What's Life Without A Little Magic!

Thermostats are the safer way to go, and are more accurate. They will adjust the temp when the room temp goes up and down. A rheostat you will have to set yourself continually.

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Mike
"Never worry about numbers. Help one person at a time, and always start with the person nearest you." - Mother Teresa