Following the cleanup of the autumn leaves that can wreak havoc in garden ponds, pond owners should immediately turn their attention to protecting their livestock, pumps and filters during the harsh winter months. Particularly cold weather can be problematic for pond enthusiasts, but knowing how to properly maintain and care for your pond during the winter period will make this time of year much easier to handle. In this guide, our pond experts will cover all aspects of winter pond maintenance to ensure your pond equipment continues to run optimally and your livestock remains healthy through to spring.
Should I feed My Fish in The Winter?
The good news is fish are well adapted to the British weather, but there are a number of steps pond owners can take to ensure their well being. As average winter temperatures dip, biological changes occur in your livestock which slows down their metabolism; meaning it takes longer for your fish to digest their food. Therefore it’s important to feed your fish less frequently to prevent uneaten food impacting your water quality – two or three times per week is perfectly acceptable as it can take fish up to three days to digest food during the peak of winter.
Changing your fish food is also essential during the winter so a wheatgerm-based pond food such as Tetra Pond Wheatgerm Sticks, which are specifically designed to aid digestion during colder periods, should be used. Wheatgerm-based food is ideal for when the water temperature is between 4°C and 10°C as they contain less protein; which makes it easier for your fish to digest at lower temperatures. However you should stop feeding your fish completely when the water temperature drops below 4°C until it warms up again when Spring arrives.
Top Winter Tip: As the temperature drops and the metabolism of your fish slows, your fish become slower moving and unable to find shelter in the absence of plants. This makes them vulnerable to herons, so you should install appropriate pond netting or heron deterrents.
What If My Pond Freezes?
If you awake to seeing your pond frozen over, do not break the ice. Breaking the surface ice in a pond sends shockwaves through the water; causing unnecessary stress to your fish which can in turn lead to fish loss. We also advise against pouring hot water over an area, as this can have the same effect as fish are sensitive to extreme temperature changes.
Silt, debris and waste continue to decompose beneath the water, producing toxic gases that can become trapped in the pond under the sheet of ice and damaging your water quality. Therefore it’s important to keep a small area of the surface free of ice to let harmful gases escape and let vital oxygen in; as leaving the pond covered for more than a couple of days can produce toxic gasses and harm your fish. So you have a couple of options to keep part of your pond ice-free.
Installing a pond heater is one of the most effective and efficient ways to keep your pond from completely freezing over and allow the gaseous exchange required to keep your fish in good health. Here at Pond Planet, we have various models of heaters available from brands such as Hozelock and Oase for this purpose and each are suitable for ponds of all sizes.
The Hozelock Pond Heater and the Blagdon Ice Vent Heater float on the surface of the pond and provide localised heat to maintain a hole free from ice on the ponds surface. The Oase IceFree 200 and Oase IceFree 330 pond heaters basically do the exact same job as that of the Hozelock and Blagdon heaters and are safe to use down to -20°C – so ideal for even the harshest winter.
The Oase IceFree 330 comes fitted with an integral thermal switch which switches the unit on automatically when the freezing point is reached and off again when the temperature goes above freezing – making it incredibly efficient and saving you energy.
If temperatures aren’t too extreme during the winter, simply aggravating the water slightly can prevent ice forming on the surface. Using a pond skimmer will help circulate the surface water to prevent ice crystals forming whilst clearing any surface debris such as remaining autumn leaves. Similarly, using equipment such as a Hozelock fish foodball will cause movement on the surface whilst providing a slow stream of food for your fish – although you’ll need to be careful not to overfeed since their metabolism has slowed.
Preparing Your Plants For Winter
As well as giving your pond a natural appearance, your plants play a vital role in maintaining a balance in the ponds ecosystem, so they should be looked after during the winter months too. Plants provide a natural filtration system that help remove toxic chemicals from the water such as ammonia, nitrogen and nitrates; whilst providing shade and shelter to reduce the stress of your fish.
The first step is to prepare your plants for the upcoming winter, and this should ideally be done towards the end of Autumn. As your plants prepare for their rest period over the winter months, they will start to lose leaves and halt their growing process. The main risk here is depleted oxygen levels in your pond as the result of decaying leaves. This is avoided by simply removing any dead foliage and floating debris from the surface of the water.
In the UK, there’s very few pond plants that will continue to thrive in the winter and the majority will die back until Spring time. However, plants such as Elodea Crispa and Hornwart are evergreen plants and will continue to grow all year round – providing much-needed oxygen over the colder months. It’s important that plants such as Water Lilies should be pruned to their lowest point so they can restart their growing process in the spring.
Do I Leave My Pump Running In Winter?
In short, yes. There are many guides online that will recommend you to completely shut down your pond pump over the winter period to prevent the water becoming super chilled as the relatively warm pond water is exposed to outside temperatures as it goes through the filter and returned to the pond, however this really isn’t necessary in our climate. The majority of these guides originate from countries where the temperature drops to much lower levels to what we experience here in the UK, and adopting the same practices here will provide more harm than good to your ponds ecosystem.
As you know, your biological filter is teeming with beneficial bacteria that help break down toxic chemicals in the water to help improve water quality and in turn improving the health of your fish. If you completely shut down the pump and filter for the winter period, you’re effectively stopping this process and allowing the helpful bacteria to die. Whilst this bacteria may become dormant in colder temperatures, supplying it with a constant supply of oxygen from the pond water is enough to keep it alive until temperatures rise again in the Spring.
Following these easy steps will provide your pond the best chance of emerging winter unscathed, ready for the return of warmer temperatures in spring and back to running optimally. To summarise what’s been discussed in the guide, here’s a checklist of actions for you to easily follow.
- Feed fish less often with wheatgerm food.
- Install a pond heater.
- Remove dying/ dead foliage from plants.
- Add evergreen plants to provide oxygen.
- Prune plants such as water lilies as far back as possible.
- Leave your pump running.