How to Prep Your Pond and Stock Tank for Cooler Weather

When the first hint of cold weather strikes, your initial thought might be to turn up the thermostat and maybe close a few storm windows. But if you have a garden pond on your property or keep animals, cold weather ushers in a bit of extra winter prep. Keeping those water sources ice-free and properly maintained for winter is an important task. Luckily, it's not too difficult. Let's explore some ways to winterize your pond or stock tank.

Winter Pond Preparation

Your garden pond is a source of beauty and joy throughout most of the year, but in the winter, activity around the pond tends to slow down. But before that happens, you want to prep your pond to make sure your aqua garden is shut down properly, not left on its own to “run out of gas" (like your lawnmower last year!). Doing this will help prevent damage to the pond's ecosystem and physical components. Here are seven things you can do to prep your pond for winter.

Cover the pond with a net.

When deciduous trees start dropping leaves and conifers drop their needles in the fall, temporarily cover the surface of your pond with a screen or netting to keep the debris out of the water and away from your fish. Otherwise, you'll end up with your pond's surface totally obscured with floating leaves, adding an extra (and annoying) step to your pond winterization efforts down the road.

Remove leaves and debris from the pond.

Once the leaves stop dropping in a month or two, go ahead and remove the net, then remove any debris that got through to the pond. Decaying leaves in the water can release an unbalanced amount of potentially harmful gases¹ like carbon dioxide. They can also decrease the oxygen level of your pond's water, which is not good for your fish.

Shut down your decorations.

Any motorized features that use pumps, like fountains or waterfalls, should be turned off. Drain all the components and properly store them for winter to ensure any remaining water doesn't burst your pipes.

Install a pond deicer.

Many pond owners overwinter fish, like koi, in a garden pond. So, it's important to prevent the ice from freezing all the way over. Your fish "breathe" oxygen and "exhale" carbon dioxide with the help of their gills, but your fish could be harmed if there is no escape route for the excess waste gases through the ice. Fish in a lake don't really have this trouble, as the lake has a large reservoir of oxygen. But your garden pond is small, and the fish need a way for oxygen to get through.

A product like the K&H Thermo-Pond 3.0 Pond Deicer will help maintain a 12-inch hole in any ice on the surface of your garden pond that's at least 18 inches deep. If your pond is more shallow, try the Thermo-Pond Perfect Climate Deluxe Pond Deicer, which will keep at least a 6-inch hole in the ice. The hole helps release unwanted gases, allows oxygen in and maintains the health of your pond's ecosystem through the winter. The pond deicers are extremely energy efficient, using a thermostat to help keep electricity costs to a minimum (only pennies per day!). The deicers are also safe to use around plastic ponds and pond liners.

Consider a greenhouse.

Some pond owners opt to install a small greenhouse-like structure over their pond to help keep heat in and cold weather out without using electricity. Depending on your climate, a greenhouse might be enough to keep the pond from freezing even without a deicer (although you certainly could run a deicer as well as a backup). The other upside is that the greenhouse effect might allow your fish to spend more days out of their winter torpor state (similar to hibernation) and give you more days of the year to enjoy them.

Get advice for your specific fish.

Be sure to research the proper water depth you need in your pond to safely overwinter your species of fish, as well as information on winter feeding or water supplements. Some fish owners even overwinter their fish indoors in aquariums.

Prep pond plants.

As with fish, you may need to take steps to overwinter your pond plants safely (moving some plants indoors, trimming back annual growth, etc.).²

Keeping a Stock Tank Ice-Free

Another aspect of winter prep involves keeping the water for your outdoor animals ice-free. This is very important because even during cold weather, your animals need 24/7 access to clean, fresh water — and a stock tank with a 1-inch skim of ice does not fulfill this need.

If you live in a reasonably warm climate and don't often see harsh winters, you can use plenty of tricks to keep the water in your animal's drinking tank from freezing. However, if you live in a colder region, you'll probably need to install a heating element. We've got six ideas you can try to help keep your stock tank free of ice.

Try a black tank.

You might recall from your school days that dark colors absorb heat while light colors reflect it. A black stock tank can absorb solar heat during the day, which might help stave off icing at night.

Use a large stock tank.

The more water, the longer it takes to freeze. If your stock tank is large enough and the temperatures don't get too cold, you might squeeze past a sub-32°F night or two this way.

Insulate the stock tank.

If you have a few DIY skills (or know someone who does), it's possible to insulate the sides of the stock tank³ just to create an inch or two of dead air space between the sides of the tank and the cold air around it. Doing this can help delay the water from freezing.

Experiment with a float.

Placing a floating object like a ball or similar item in the stock tank may also delay the water from icing. As wind moves the ball around, it creates small ripples on the surface of the water that may postpone freezing.

Caution: Only try this if the object does not startle or scare the animals, as you don't want to discourage them from using the tank because they're afraid of the object.

Use a stock tank deicer.

Even with all these methods, the stock tank water will still freeze if temperatures are cold enough for extended periods. In that case, just bring a simple heat source to the rescue!

A stock tank deicer like a K&H Ultimate Stock Tank Deicer can be inserted directly into the water to keep the tank ice-free even in very cold conditions. The deicer uses heating elements to keep the water from freezing and is controlled by a thermostat so that the device only uses power as needed, reducing your tank heating costs. An option like this is extremely practical for locations that experience seriously cold winters. You can also find five-gallon water buckets with self-contained heating elements.

Bonus: Try a heated hose!

It's frustrating to go outside to fill the stock tank on a frosty morning only to discover the hose is frozen solid and won't flow. A heated hose like a K&H Thermo-Hose Outdoor Heated Hose eliminates this problem — just plug it in about 20 minutes before you need it, and the ice is gone. Something like this makes life easier — and that's something all farm folks search for!

Winter weather isn't so bad once you're prepped for it, and while you're cozy indoors on a wintery day reading a good book, your fish and livestock will appreciate the extra work you did to prep them for winter, too.

1. Salvatore, Frank. Koi Pond HQ. “Frozen Koi Pond." https://koipondhq.com/frozen-koi-pond/

2. Grant, Amy. Gardening Know How. “Winterizing Water Plants: Care Of Pond Plants Over Winter." Apr 2022, https://www.gardeningknowhow.com/ornamental/water-plants/wgen/winterizing-water-plants.htm

3. Shouse, Shawn. Iowa State University of Science and Technology. “Protecting Water from Freezing." Nov 2016, https://www.extension.iastate.edu/smallfarms/protecting-water-freezing