API 8PB Pond Breather Heated Aerator, 40 Watts Vents harmful gasses from frozen ponds Floats in pond and freezes into ice up to 15 inches thick Energy efficient: Pond Breather operates on 120 volts, 40 watts, and uses 31 times less energy than 1250 watt de-icers Exposes 4,000 to 10,000 more surface area of water than conventional heaters and de-icers With a gentle current to move oxygen throughout the pond, Pond Breather uses just enough heat to keep water flow open