Things You'll Need
- Fish pond
- Pond food
- Small skimmer net
- Water thermometer
- Leaf netting (optional)
- Pond heater (optional)
- Airstone (optional)
Instructions
Determine the acceptable range of temperatures for your fish. Goldfish and koi are cold-water fish, so they can live as long as the pond is not completely frozen.
Set a feeding schedule for your fish. You should add no more food per feeding than the fish can eat in five minutes. In addition, fish stores sell food especially for cold climates and the less-capable metabolism that results from living in cold water. Follow the instructions; most cold-water foods are suitable for water temperatures of 45 to 60 degrees, reports The Water Garden. Any colder than that, and you should not feed them.
Monitor the pH, ammonia, and nitrate levels weekly. Ammonia is a potentially poisonous waste product that settles at the bottom of the pond, and under freezing conditions it may concentrate in the bottom of the pond where fish hibernate. Introducing duckweed or other hardy plants to the system can reduce ammonia levels and increase oxygen levels, according to USDA reports. Fish eat duckweed, so if you introduce it into your system, you can reduce the food allowance. A frozen pond may also require an airstone to properly distribute oxygen or even an air pump, says Pond Market.
Change the water regularly, at the rate of about 20 percent every month. Use a netting-covered bucket or pump so that the fish stay in. Also remove debris such as falling leaves, using the skimmer net. Installing leaf netting over the pond also keeps out debris and predators away.
Plan ahead for winter. Northern climates will likely require a water heater or pond de-icer to ensure that the pond does not completely freeze, and even warm areas sometimes see extremely cold winters. Research the temperature tolerance of other inhabitants of the pond, such as snails and plants. Reduce water circulation during the winter so that cold freezing water remains at the top and the pond does not freeze through, according to an article in Water Garden.