Pond pumps and filters play an important role in the general health and well being of a pond. With the arrival of cold winter months their role changes. In this articles we will look at how to winterise a pond. Pond plants and fish have different needs in winter versus the other seasons of the year. By following a few simple steps your pond can be kept in a good condition through the winter months.

Pond fish feeding 

For fish pond owners, knowing how to care for your fish in winter is important to keep them free of disease, oxygen depletion and below threshold water temperatures. 

When the outdoor temperature drops below 10 degrees, this is the time to stop feeding your Koi and gold fish. Feeding your fish through winter, even small amounts will have a detrimental affect on their health as well as on that of the pond water. The reason why is that certain enzymes and bacteria which breakdown the food in the digestive system of fish, thrive in warm weather but their presence decreases significantly when the temperature gets colder. Therefore, any food fish eat in the winter months will pass through their digestive system without getting broken-down due to the lack of these enzymes and bacteria. Undigested food could either cause blockages in the fish gut or start to decay inside the gut risking bacterial infections which could then lead to fatalities.

Many pond experts recommend that the pond pump and filter are kept running through the winter months to keep the pond oxygenated. But, for fish pond owners this is not ideal when the temperature drops to, or close to freezing and here are the reasons why:

• If your pond pump is kept on through winter it will cause the water temperature to drop rapidly and to lower temperatures. The pump will take the cold surface water and circulate it down to the warmer layer at the bottom of the pond where fish are hibernating. Your fish may then suffer from cold.
• Keeping the filter clean over the winter months may prove difficult. If it isn’t done routinely it will get clogged with debris and put strain on your pond pump.

If your pond is not prone to freezing over and you decide to keep your pond pump and filter running through out the winter, it is advisable to raise your pond pump closer to the surface. This will minimize the mixing of colder water at the pond bottom with the warmer water closer to the surface, which could adversely affect your fish. 

If your fish pond freezes over then melt a sufficient area to allow the flow of oxygen and escape of toxic gases (skim off fallen leaves and debris before they sink to the bottom of the pond to limit decomposing waste matter and resulting toxic gases). If you don’t have a pond heater, then take a pot of boiling water and place it on the sheet of ice (don’t let go of the handle!) or float a ball on the surface of the water. Either way, don’t hammer the ice to crack it because the shock waves it causes can harm fish.

Pond plants in winter

Most potted plants winter-over well if the have been cut-back almost to the roots before temperatures drop below 10 degrees. Plant life can also be a source of debris. As marginal and deep-water aquatic plants begin to die back, prune dead stems and leaves to prevent decay in the water during the winter.

Pond plants still require enough daily sunlight to photosynthesis and replenish oxygen levels so cut plants back if they are covering more than three-quarters of the water surface. 

Continue to skim off dead leaves and debris throughout the winter period to prevent debris build-up at the bottom of your pond.

Follow these steps for a healthy pond to start Spring off in your back garden.

For pond pumps or other pond equipment contact our experts at Liners Online.