I've been having issues with keeping my temps up lately, its been pretty cold the past couple of weeks, so they are lower than normal. With a heat lamp and UTH in a 10 gallon tank, i get a reading of about 80 degrees on the warm side. I have read the sticky on glass tank setup, and have adjusted the screen lid with foil on the bottom and duct tape on top, but it doesn't seem to help. I've been thinking of buying a thermostat as well, but they are pretty expensive, is there anything else i can do?