Originally Posted by reybie
Question for you electronics gurus. Since you're already using an arduino board already, is it possible to integrate a temperature sensor in it that can switch a relay on/off to say power a fan or heater?
I was browsing the arduino forum briefly today and I don't think there's a waterproof temp sensor (yet).
You could probably just take a cheap temp sensor IC (LM35, etc) and then encase it in a tube.