I finally got some heated bowls and a heated fountain and they have made all the difference. They keep the water liquid in all but the worst of the cold. Even when they do start to freeze, usually it only takes a tap or two to dislodge the ice and it melts again. The downside is that you do have to have some type of electric in your coop. However, I did just find out about a no electric trick that seems to work to keep the water liquid. More on that one at the end. For now, Lets talk about the types of heated chicken waterers that I use.
Heated dog bowl: This is the one I have in the 2 largest coops. It holds 5 quarts. There are about 35 guineas and chickens in the biggest coop. I fill this once in the morning. Very rarely does it need more water before bedtime but I often splash a bit in just so they don't run out before I get out to see them in the morning. This is super easy to clean because it is so wide open. Unfortunately it also gets shavings kicked in it sometimes for the very same reason.
I bought 3 of this one and I've had them about 6 years and they still work great. They kept the water completely liquid except for a few times when it was like -10°F! Even then, only the edges iced up and there was still plenty of space in the middle for the chickens to get a drink. If you use one of these you'll want to put something under it in case of splashes I use a water heater pan. They're not terribly expensive and are sold in just about every hardware store.
Heated plastic poultry fountain: This one is now in the Silkie coop but for the last 3 years it sat outside the d'Uccle coop in the winter. The main problem I have with this one is that it has a very short cord, so even if you have electric in your coop you might need an extension cord. When I had it outside I had it attached to an all weather extension cord and it worked great, even when the snow was a foot deep. (I didn't know that that is not exactly recommended by the manufacturer, so take that idea with a grain of salt)
Occasionally when this one is full and it's really really cold, the top of the water will freeze. As the chickens drink the water level drops and the frozen part just kind of hangs there at the top. I just tap it a few times and the ice falls into the water and melts. It's said to keep water from freezing down to 0°F, but it's still worked for me in colder weather. One of the nice things about this is that it has a rubber plug in the base to fill it, so you're not trying to match up the top and bottom like some other gravity drinkers I have. Since this one only has a trough for the chickens to drink from, if shavings get kicked in you can just dump them out without having to refill the whole thing.
One heated water option I haven't tried is the metal Heated Base that you can buy for the metal drinkers. For one, it was the most expensive option when I was purchasing the ones I have. Secondly, I don't have metal waterers so I would have had to purchase those too. However if you do have that type of waterer already, then this might be a good option for you. The downside of this one (besides cost) is that it only keeps water from freezing down to 10°F.
Good luck fighting the cold!
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