A pond heater allows fish to overwinter in their outdoor pond by ensuring a hole is maintained in the ice for exhausting gasses from the pond. Pond heaters operate with built-in thermostats to melt a small hole in the ice for low electrical costs. Maintaining a hole in the ice ensures the pond does not freeze solid in cold US climates. Goldfish and koi can survive outside in most ponds if they are properly winterized and a pond heater is an essential tool.
The 100 Watt ThermoPond heater is ideal for smaller water gardens and backyard ponds up to 500 gallons. The Perfect Climate pond heaters will keep a larger area open in the ice and are best for larger ponds. Multiple heaters can be used in bigger basins.
The open area created by the heater can be used to introduce a bubbler diffuser via a small air pump into a pond to add aeration during the long winter and to ensure that ammonia levels to not build up.