I have the same problem. Here in Newfoundland it's usually -30 or so at night. I'd suggest an under-substrate heater on one of the sides of the tank. Did wonders for me, and the heat never wavers below 82 during the day, 72 during the night, even if it's blowing a gale and -35 outside.

Hope that helps.

[ Reply To This Message ] [ Subscribe to this Thread ] [ Show Entire Thread ]