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What do you really mean when you say fish are “dormant” for the winter? Do they sleep? | Decorative Ponds & Water Gardens Q & A

Q: What do you really mean when you say fish are “dormant” for the winter? Do they sleep?

Q: What do you really mean when you say fish are “dormant” for the winter? Do they sleep?

Diane – Wells, ME

A: When the days shorten and temperatures drop, koi and other pond fish enter into what’s called torpor, or a period of decreased physiological activity that allows them to save energy. They don’t sleep the winter away, but they do essentially hibernate—their metabolism slows, they require less food, their activity level drops and their body temperatures reduce.

How do they know they need to hibernate, and what can hobbyists do to make their finned friends’ winter torpor restful? Read on to learn more.

Mother Nature’s in Charge
Fish don’t use calendars to decide when to take their winter snooze. Instead, they follow Mother Nature’s lead. Because fish are cold-blooded, their metabolism reacts to the external environment. When the water temperature falls, so does their activity level: Their appetite dwindles, they digest food more slowly, and they expend less energy. In the spring when temperatures warm back up, the fish will naturally come out of their torpor. They’ll start to seek out food as their metabolism increases, and they’ll become active once again.

Suspended Animation
You’ll know when your fish go dormant. They won’t lie down on the pond’s bottom or curl up in their cozy Koi Kastle, but they will float upright, tuck in their fins and remain suspended in the water. As the fish hover there, you may still see some super slow movement, and they may also wind up facing in the same direction as if they were heading somewhere at less than a snail’s speed.

Sweet Dreams, Koi!
Here are four ways to give your koi a peaceful winter rest:

  1. Set up an aeration system to keep the water pumped full of oxygen. Even though they’re hibernating, your fish will still need some fresh O2.
  2. Install a de-icer to keep a hole open in the ice and allow for gas exchange. If the pond freezes over, use warm water to reopen a hole; do not bang on the ice to crack it, as doing so can stress your fish.
  3. Keep as much debris out of the pond as possible to prevent muck buildup over the winter.
  4. Let the fish be. Don’t try to get them to move or swim or wake up from their slumber. Keep an eye on them, but leave them alone until they wake up on their own.

Pond Talk: Have your fish started hibernating yet?

Vent Harmful Gases All Winter - Airmax® PondAir™ & Thermo-Pond De-Icer Combo

 

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Do I need to heat the water in my pond in order for my fish to survive the winter? | Decorative Ponds & Water Gardens Q & A

Do I need to heat the water in my pond in order for my fish to survive the winter?

Q: Do I need to heat the water in my pond in order for my fish to survive the winter?

Kimberly – Bradford, PA

A: We all love central heating or a roaring fireplace in our homes when winter’s chilly temperatures roll in, but your pond fish—specifically your koi and common goldfish—don’t need those creature comforts to stay happy and content.

Cold Temps and Torpor

During the winter months when the water temperature is 45 to 50 degrees Fahrenheit and below, koi and goldfish enter into a dormant state. The technical term for this is torpor, and it means that the fishes’ metabolism and activity slows, they become very lethargic, and they require little nourishment. In this state, the koi and goldfish will, in fact, be quite comfortable in temperatures as low as 35 degrees.

Demystifying De-icers

If koi and goldfish don’t need the water warmed, what’s the deal with pond heaters and de-icers, like the Thermo-Pond, Farm Innovators or Perfect Climate™ de-icers?

These tools of the trade aren’t intended to turn up the heat in your pond’s water. They’re designed to simply melt a hole in the ice, which allows dangerous gases to escape while letting fresh and life-sustaining oxygen. When plugged into the Thermo Cube® Thermostatically Controlled Outlet, the de-icers will turn on when temps dip to 35 degrees and off when temps rise to 45 degrees on their own. To save even more on energy costs this winter, consider installing a PondAir™ & Thermo-Pond 3.0 aeration and pond de-icer combo. When used with an aeration system, you can use a lower wattage de-icer which will not need to be ran as often to maintain an open ventilation hole.

De-icer’s Limitations

But the one thing de-icers don’t do: actively circulate or move the water like an aeration system does. That agitating action is necessary to trap and bring oxygen into the pond’s entire water column—including the bottom, where the fishes are snoozing. It also helps to prevent ice from forming a complete sheet on the pond surface.

Though running a pump will help move the water, it doesn’t agitate it enough to get those O2 levels up. A pump also costs more to operate than an aeration system, and, if ice does form, you could do some major damage to the unit from poor water flow. If you do not yet own an aeration system for your water garden, the PondAir™ & Thermo-Pond 3.0 Combo is a surefire way to protect your fish this winter.

Pond Talk: How do you keep a hole in the ice on your pond or water garden during the winter?

PondAir™ & Thermo-Pond 3.0 Combo - Protect Your Fish This Winter