You can use a heating mat (seedling or reptile) on a cinder block instead of a 250W stock tank heater if you want to save power costs. I've put a 2 quart drinker with a horizontal nipples on a seedling heat mat and it never froze even once last winter. Temps got down to -18 F and it was just fine. I was using that small of a container because I only had a trio of polish in that pen. I get my HN from Susan at Allboutchickens.com. She imports directly from Europe and has the best prices if you want more than 5. If you just want 5, Rich is a nice guy, too.Why would the horizontal nips work better, would i need to run that line to the nip. I have vertical nips with a 5 gal bucket and a 250watt stock tank heater the water is liquid but the nips are frozen. 12 degrees this am and they were frozen. Chickens got their first taste of snow yesterday, 4ft in 36 hrs gotta love buffalo!