How To Prepare Your Pond For Winter

Feeding Fish in Winter

As winter approaches and water temperatures drop below 10°C, it’s crucial to adjust your fish-feeding routine. Fish metabolism slows in colder water, making them less able to digest food efficiently. Overfeeding during this time can lead to health problems, as undigested food can rot inside the fish. Therefore, it’s advisable to reduce feeding frequency gradually and stop feeding entirely when temperatures fall below 4°C to 5°C. Specialized cold-weather fish food can be used if necessary, but general feeding should be minimized to prevent excess waste accumulation in the pond.  

Clearing and netting your pond

It is important to remove all debris from your pond during this time to prevent sludge from building up in the bottom of your pond. This can be done using a fine net or pond vacuum. Netting your pond is a crucial step for your winter pond prep. It is especially important in areas surrounded by trees, as decaying leaves can contribute to sludge buildup and nutrient overload in the pond. Additionally, netting will serve as a protective barrier against predators, such as herons, which can pose a greater threat to fish during winter when their natural food sources are scarce.

Managing Pond Filters

The decision to keep pond filters running during winter depends on various factors, including local climate and pond size. Running filters can prevent the water surface from freezing and ensure continuous oxygenation. However, this can also lead to temperature fluctuations in the pond. If filters are left on, it’s advisable to adjust the pump’s position to minimise disturbance to the warmer bottom layers where fish tend to reside during winter. If you live in a cold climate where the pond is likely to freeze over, then turn off equipment. This is because the fish will hibernate in the warmer water at the bottom of the pond. If turning off the filters, do so after fish feeding has ceased, clean them thoroughly, and store them in a dry place to prevent damage.

Generally, in the UK you should be fine to leave the pump and filter running as normal.

Preventing Ice Formation

To maintain a healthy pond in winter, it’s important to prevent the surface from freezing completely. A frozen pond surface can impede gas exchange, leading to oxygen depletion and the accumulation of harmful gases. A pond heater is an effective solution to keep a part of the pond surface ice-free. Alternatively, a simple method like placing a tennis ball on the water surface can help create an opening in the ice, allowing for necessary oxygen exchange.

Winter Pond Treatment and Water Testing

Regular water testing is vital during winter to ensure the health of your pond. Testing for pH, KH, GH, nitrites, and nitrates helps maintain a balanced aquatic environment. To stabilise your water parameters, use a product such as Envii Pond Equaliser. During colder months, water conditions can become harsher, making diligent monitoring and treatment even more important. Using a bacteria-based winter pond treatment, such as Envii Winter Pond Treatment, can help maintain water clarity and target the sludge and debris accumulation at the pond’s bottom, thereby ensuring a healthier environment for aquatic life.