Toxic gases caused by decaying matter and fish waste can become trapped under the ice. The TetraPond® De-Icer is a winter survival solution for fish, keeping an area of your pond ice-free to allow harmful gases to escape through the opening. The energy-efficient thermostat control shuts off power when not needed. The natural stone finish blends with your pond’s surroundings. This 300-watt device is effective down to -20 degrees. Includes a 3-year limited warranty (see product packaging for details). UL Listed. Never break the ice to create an opening in ice on the surface of your pond – you’ll risk causing harmful shockwaves that can injure or even kill your fish. In extreme cold areas, where ice cover lasts for a long time, install a bubbler in addition to your de-icer. Keep the bubbler close to the surface of the water —like its name suggests, a bubbler produces thousands of bubbles that replenishes valuable oxygen in your pond, helping your fish survive. Since 1951, Tetra has developed the world’s most comprehensive body of fish food knowledge, and fishkeeping enthusiasts have looked to the brand for products and solutions that add ease and beauty to their home. Whether you're an experienced hobbyist or just starting out, Tetra has everything you need – from a large variety of quality fish food and innovative equipment to test kits and decor.