Hi Roberta,
last winter we got an electric water heater, it's just a metal platform that you set the waterer on, it plugs in and does the job. I'm not sure if we'll purchase another for our new coop, dh picked up some electric buckets we might try. I think we paid around $30 for the platform unit. I use it unplugged during the rest of the year to keep the water elevated and cleaner due to less litter being kicked in.

The aquarium heater sounds like it wouldn't work with your current setup unless you put one in the 5 gallon bucket and another in the hanging waterers, or you could use the platform kind for the floor waterers. It is a royal pain dealing w/water in the winter. We have to shut our outdoor source off so I haul the water from the house out every other day. Now with the added coop and ducks it is going to be a pain. I need to find some really warm waterproof gloves!

-Sheila

The chicken water I just carry and swap out waterers. I haul a hose in and out of the basement to fill the horse and goat water.
They do make base heaters designed just for poultry water. Fish tank heater is going to be severly taxed outside and I'd think it would be a fire hazard. They are designed to raise the water temp a few degrees in house enviorment and not to thaw things in a northern winter.
Sometimes I cheat and take a bucket full of water out of the big stock tank. Fill the chicken water that way. My big stock tank has a heater in the drain plug that the horses can't reach to mess with.

I've heard of people using a heated dog water dish inverted to save a few dollars. I'm a chicken at heart. Afraid of fire. I don't want to skimp. Have everything roast and find the insurance company says too bad you were using electric things for purposes they weren't designed for.

If you can hang a simple heat lamp securely over the bucket it would probably work on all but the coldest days. Just have to remember that chickens get curious or get frightened and fly. Have to make sure that lamp isn't going to hit anything should it get swinging or worst yet knocked down into hay and shavings.

Fire, think fire.

They do make neoprene winter gloves. Same stuff as wet suits for diving. Good ski gloves will give you warmth without the bulk.

Most of us up here just change our watering habits during the deep freeze.