I can't imagine changing water that often even in the warmth of the summer! Wow! I use a bucket that is suspended from a post with nipples not the underside. I throw an aquarium heater into the bucket (it's a small, shatter proof one) that lays on the very bottom. It is connected to a timer that cycles on and off in 30 minute intervals. Easy peasy. Our temps are to bottoms out at -9F tonight and it was 2 last night...the water never froze.