Rhiahl: This is a really good idea... Unfortunately, won't work in -30 weather :) It gave me some ideas though..... Maybe if I move back down south.
TooSlow4U2: Thanks for posting this tutorial up for us. I actually watched this a few times this last summer while trying to come up with some sorta idea of what to build but just now got everything together and I built virtually the identical warmer that you built. It is just now getting down to freezing temps at night here in southern Indiana. I presently have a 1" thick piece of flat limestone being used for a cap as an insulator between the flu pipe & the actual watering container but I'm having some issues trying to figure out the bulb size to use or at least the easiest way to control the temperature. With a 100W bulb, the limestone cap is barely transferring heat. With a infrared heat bulb (red glow type) being used inside, the limestone cap reaches almost 455 degrees when checking it with an infrared temperature probe device. I may try a regular flood lamp bulb next just to see how that works. I thought about getting a "thermo-cube" to try too.
Dylan Meier: how cold does it get where you live?
HOSS-IT-IS: I put my lamp in a fire place flue it is the inter liner in a chimney. then I put a piece of aluminum on top I had to replace the piece of concrete pad I had on the top it did not transfer heat good my water was still freezing. so I put the piece of aluminum.and that did the trick.
Tom Thao: Just wondering do electric supply have pot or where do you get your pot cement to sit heat lamp in?
couerl: Great idea, I bet it could even be simpler than that, an extension cord and an old lamp or something.. Gonna think about this some more..