What type of waterer do you have set up? If you are keeping it in the coop, you want a more closed system as something like a heated dog bowl waterer will add a lot of moisture to the coop which you certainly don't want.I definitely do not want them to stress and will let the light be what it is without adding additional. The heater for the water will be inside the coop to keep it protected from the elements. I agree they are animals and just want to keep them happy.
This is what I made. The bucket is food grade and cost less than $4 and the bag of 12 horizontal nipples I got off Amazon for $11. I did add some Teflon tape to the threads. You just drill 11/32" hole in the bucket and thread in the nipple. It keeps the water perfectly clean inside the coop. I just place the lid loosely on the top. My chickens don't stay in the coop other than for sleeping, egg laying and getting a drink so I've not had any problem with them perching and pooping on the lid. I bought a used thermostatically controlled bird bath heater that is safe for contact with plastic that I will put in it for the winter. You can also use a low watt aquarium heater that is secured inside a metal cage to keep it from touching the bucket to keep the water from freezing. This is just one closed system, easy to maintain winter water option for those who have access to electricity in their coops.
