We've already had several days cold enough to freeze the water, and I have just been taking fresh water several times a day. But the winters are long here, so that is not a good solution and I am getting nervous that I haven't figured out another option. I had hoped to find some small solar option, but when my search turned up nothing, I purchased a heater intended for a metal double wall fount at fleet farm. I went to install it, and saw that the instructions explicitly say to not use with an extension cord. Our coop is a ways from the house (haven't actually measured), but could certainly be reached with one 100ft extension cord. Say we attached it to a GFCI outlet and put the extension cord in metal tubing and wrapped seams in electrical tape, what safety issues would I still need to consider? Also to note, this is the only item needing electricity at the coop. Thanks!