Okay I posted that I had put the heat base from a heated waterer. Under my bucket with horizontal nipples. It has done great to about 15 degrees or so. But after that the water that is left in the little cup freezes and locks up the nipple, even though the water in the bucket is not frozen at all. Every night lately I am out there with vasoline, or now at someones suggestion, bag balm. Do have some frostbite on comb tips, but with it going to -22 I am not really sure there is anything I could have done. Along with my container of salve for their comb, I take an old raggedy towel, (mess job to say the least). Last night I was leaving and looked down at the bucket of water, yup a touch of water in each cup. Started to leave, gathered my things, picked up my towel. Duh! I touched the towel edge gently at each nipples cup with out bumping the the silver tip to release more water, it soaked up everything in the cup. Well I thought we will see....this morning, no frozen nipples! And cold enough last night to have done it. Will keep trying and see but it makes total sense. Took me what 10 seconds? and that meant I didnt have to drag out another 5 gallon bucket of water in the morning and bring that one in the thaw! woo hoo. Oh and hubbies gift to me at Christmas, a LED head lamp! I was propping my phone with the flashlight on it turned on to do my evening check and comb care. Perfect gift!