It's easy enough to say make it deeper, but the man needs something now, not next spring. Brandonsdad, I'm assuming that your winter is not that much different from ours here in the Great White North. I use a 1500w stock tank de-icer, which is thermostatically controlled to come on at 33 to 35 F. However, I think it would stay on full-time for most of the winter, so I only plug it in once the ice has covered the pond for about two days, and unplug it when the hole in the ice is about 18 - 20" across. This means that it runs for about 4 -5 hours twice a week. Personally, I don't believe a 150w. heater would work at our temperatures, and a lightbulb under a tarp would be history the first time a droplet of water hit it. And by the way, my pond is 2' deep, and the first winter (no fish) it froze solid. with the de-icer I get about 8" of ice at the edges. John