Outdoor catfish pond in UK?

[Hayabusa]

As the title says really, anyone have an outdoor catfish pond with redtail and/or tiger shovelnose in?

How do you keep it warm through the winter etc if so?

Thanks in advance, just having a bit of a brainstorm after I jokingly said to the mrs we could have one and she said "yeah"

 

[Hayabusa]

Having said that anyone in any colder climate country, hmmm, how do I edit the title of the thread?