120-Watt Thermostat-Controlled De-Icer with 18 ft Cord

When pond ice seals completely, fish waste and decomposing organic matter produce ammonia and CO2 that build up under the surface with nowhere to escape. The Pondmaster 120-watt floating de-icer keeps a small area of open water through even the coldest Canadian winters, letting those gases out and oxygen in. The built-in thermostat cycles the heating element on and off automatically, preventing overheating and reducing power consumption.

Winter Fish Protection

The de-icer does not heat the entire pond. It maintains a breathing hole, typically 12 to 18 inches across, in the ice surface. Fish cluster near this opening in winter, and the open water prevents the toxic gas accumulation that causes winter fish kills. At 120 watts it is adequate for ponds up to 1,000 gal (3,800 L) in most Canadian climate zones; larger or exposed ponds may require two units or a higher-wattage model.

How to Use

Float the de-icer on the pond surface when daytime temperatures consistently drop below 0°C (32°F). The thermostat activates the heating element when the water at the surface nears freezing. Do not run in ponds under 12" (30 cm) deep; the element must remain submerged. Remove and store after ice season ends and water temperatures stabilize above 4°C (40°F).

Ideal for koi and goldfish ponds up to 1,000 gal (3,800 L) in central and eastern Canada where complete freeze-over is a regular winter event.