[nathankaye]

Thanks Paul but i am renting so  dont want to be doing all that.

Might try a 2kw or maybe just forget about it, how many times does it drop below freezing afterall.

Some people use them aquarium heaters, you just plug it in and drop it in the tank. could be an idea?

I did that with several heaters. I used four in the end 2 in each side of the baffle. It took the water to about 40 degrees. So it was nice with the hose.
Absolutely hate stiff cold hoses in winter time