I looked into getting a pond heater, but I wasnt prepared to spend
$200.00, I'll just have to check more ofter withthe airline as it seem to
work when its working.

Joel - as Ross said, go to TSC or another farm co-op store and ask for a
floating heater for livestock water troughs - they run from $30 - $50 and
are 1250 or 1500 watt floating heaters . I don't use one as my airstone
works fine as long as I keep an eye on it - If I used one I would have it on
a timer and run ~ 2 hrs /day ( I had one 10 yrs ago and only plugged it in a
few hrs at a time on really cold days) . They do like their hydro
Gale :~)