[JackieW]

If you keep your pure water storage tank outside how do you prevent it freezing up in sub zero temperatures?
I am setting up my system in a confined indoorish area but there is easier access outside under a balcony. But I am wondering if it will freeze in winter. A relative has suggested a 'nutrient heater' such as

http://www.growell.co.uk/heavy-duty-nutrient-heaters.html#tabs

[colin purewater]

No point heating a ibc out doors just let it freeze but keep a pipe in it
To pump though the top.

1st few inches may freeze so chuck a few kettles of hot water over it

If will be find mate

[LBWCS]

very hard for the inside of an ibc to freeze. as long as the hose is empty dunk it in the top 

[d s windowcleaning]

When we had that really bad winter a couple of winters back i was just moving house and was in a rush to set my static system up , The tank was outside and it took days before i was able to fill a 400 ltr tank from this it was just a solid block of ice . The tanks still outside but now boxed in and insulation all around the tank , hopefully this will work if not then im having a few days off .

[richard jagger]

Insulate with rap around silver insulation. and drop one of these 1000 watt heaters in it worked for me for the last two years and my water was always 33 degrees.

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=fish+tank+1000watt+heater

[Mist A Bit]

Even when it was -15 a few years back i just smashed through the ice so my submersable pump could go in, job done and off to work