Do I Need to Empty My Fish Pond When the Temperature Gets Below Freezing?
In areas where temperatures stay below freezing, winterizing your pond is essential, but you don’t necessarily need to empty it. Instead, start by considering these factors:
Depth Matters: If your pond is at least 3-4 feet deep, the bottom should remain above freezing, even in the coldest climates, providing a safe zone for fish. Shallower ponds are at risk of freezing solid, which would kill your fish.
De-icing: Even while fish are in a state of torpor, they need to “breathe,” and harmful gasses are continually produced by decaying organic matter. Installing a floating de-icer or a simple aerator ensures a portion of the pond’s surface remains open, allowing the harmful gasses to leave and be replaced by oxygen.
Fish Care: Reduce fish feeding as temperatures drop and stop entirely when the water temperature remains below 50°F (10°C). Fish become less active, and their metabolism slows dramatically as they enter torpor, making digestion harder. They don’t hibernate, so don’t be alarmed or tempted to feed them if you see movement in the depths.
Plant Management: Trim back and remove dead or dying aquatic plants. Some hardy plants will survive submerged below the ice, while others might need to be brought indoors or discarded.
Equipment: Turn off and remove pumps and filters to prevent damage from freezing and cracking.
All fish are cold-blooded, but only some species are suited to overwintering. Among decorative fish, koi and goldfish can survive, as well as a great variety of sport fish that regularly endure cold winters in the wild.
Should I Leave my Pump and Filter in the Fish Pond During the Winter?
Whether or not to leave your pump and filter in the pond during winter largely depends on your local climate and the specific equipment you have.
Removing the pump and filter is generally advised if your area’s temperatures drop below freezing, since any remaining water can freeze to and lead to damage or cracking of the equipment. Instead, clean and store them in a dry, frost-free place.
For ponds with fish, consider using a pond de-icer or aerator to maintain an open area on the pond’s surface for gas exchange. This open area ensures harmful gases from decaying matter aren’t trapped underneath the ice, providing a safer environment for your fish.
If you live in an area where winter temperatures don’t drop below freezing, always keep your pump and filter going when fish are in the pond.
What Can I Use to Heat Pond Water During the Winter? I Don’t Want My Fish to Freeze!
Fish adapted to cold climates, like koi, goldfish, and other carp varieties, will be perfectly happy in a properly winterized pond, even under thick ice. Trying to maintain warm temperatures during winter could stress them more than if you allow them to enter torpor. If your fish population includes warm water or tropical varieties and the water temperature is likely to drop below their preferred range, it’s a better idea to move them indoors during the winter.
If you choose to heat your pond, there are submersible pond heaters capable of raising the water temperature of small ponds. Still, aside from the expense, they’re probably unable to provide enough power to heat a large volume of water. In addition, it’s very stressful for fish to encounter significant temperature differences, so you’d need to use a powerful pump to maintain rapid enough circulation that the heated water is quickly mixed with the rest of the pond.
Overall, unless you live in a climate with mild winters that can keep the average water temperature very close to the normal range, trying to heat your pond is likely to be an expensive prospect that could, ultimately, harm your fish.
Is a Net Over My Fish Pond Necessary?
Using a net over your pond is not mandatory. Even so, it offers several benefits depending on your specific circumstances:
Debris Control: One of the primary reasons pond owners use nets is to prevent falling leaves and other debris from entering the pond, especially in autumn. Decomposing organic matter can contribute to water quality issues, such as increasing nutrient levels that promote algae growth and potentially causing oxygen depletion.
Predator Deterrence: A net can deter predators like herons, raccoons, and cats by making it harder for these animals to access your fish. It serves as a simple and inexpensive yet effective protective measure.
Safety: In some settings, especially with households having small children or pets, a sturdy net could provide an added layer of security, reducing the risk of accidental falls into the pond. If you depend on a pond net for this situation, ensure it is anchored securely, and the mesh is fine enough to prevent injury if fingers get entangled.
Jumping Fish: When startled, some fish species may jump and land outside the pond. A net can prevent this inadvertent escape.
However, while nets are beneficial, they can obscure the view of the pond. They also require regular cleaning to remove accumulated debris. The decision to use a net should be based on evaluating these pros and cons and your pond’s specific needs and aesthetics. Some pond owners choose to set up nets only during certain seasons or conditions, which may be a good option for you.
Should I Feed My Fish During the Winter?
Feeding fish during the winter requires understanding their metabolic changes in response to colder temperatures. As water temperatures drop, the metabolism of pond fish, especially cold-blooded ones like koi and goldfish, slows down significantly. Their digestive systems nearly halt entirely when the water temperature is consistently below 50°F (10°C).
Feeding regular fish food in these colder conditions can be problematic. Suppose the fish consume the food but cannot properly digest it due to their slowed metabolism. In that case, the undigested food can decay inside them, leading to severe health issues. Moreover, uneaten food can sink and decay in the pond, reducing water quality.
In mild climates where water temperatures cool but don’t freeze, fish still experience a reduced metabolic activity, albeit not as pronounced as in colder climates. In this case, regularly monitor the water temperature. Generally, when the water temperature remains below 55°F (13°C), you should reduce feeding frequency and quantity and switch to a low-protein, easily digestible, wheat-germ-based fish food. This type of food is formulated for cooler temperatures and is easier for fish to process when their metabolism slows.
When in doubt, fish behavior can be a good indicator of their feeding needs. If they are less active and not coming to the surface to feed, it’s a signal to reduce or temporarily halt feeding.
