How to keep water from not freezing pics plz

[Ravinrascal]

I am looking to make a rainwater watering system but I am worried about it freezing in winter. Also if you don't mind could you view my page and see if you can help my coop improvements

 

[brains]

Interested in this too
Thanks
Ed

 

[chfite]

I use a bird bath heater to heat the water supply in winter. One such as this: http://www.bestnest.com/bestnest/RTProduct.asp?SKU=API-BDT250
is available many places. It is built like a tank.

Chris