The Laguna Power Heat 500 watt De-Icer will keep an area thawed and open in the pond, allowing the release of toxic gases from fish respiration and decomposing organic matter to escape.
At the same time it allows oxygen to re-enter the pond. Safe for plastic and liner ponds, the pond de-icer will not harm fish or plants. The heater has dual zone integrated thermostats to help the heat distribution. Suitable for garden zones 1 to 8 (-6 ºC / 20 ºF and below).