Immersion Heater to hear pond?

[muskieboy]

Do you think it's possible to heat a pond with an immersion heater (the thing in those electric water boilers). I reaches a much higher temperature compared to an aquarium heater and is only 300-500 watts. All you would need to do is hook it up to a thermostat and make a guard for it so the fish don't get burned.

Do think this would work?

http://www.ebay.ca/itm/Mini-Portabl...609?pt=LH_DefaultDomain_0&hash=item3cb24c21d9

http://www.ebay.ca/itm/Norpro-559-I...all_Kitchen_Appliances_US&hash=item4600b8a017

EDIT: meant to say heat in title