« »

Winterizing the Pond


Just received this common question regarding winterizing the pond:


“I do have a problem and I am hoping you can help.  I live in Columbus, Ohio and my pond is approximately 10’x10′ and 2′ in depth with a waterfall/stream.  I am having difficulties keeping the pond from freezing over and/or keeping a whole in the ice.  I have tried multiple solutions like:

1) Running the pump/waterfall through out the winter hoping the moving water would prevent the freeze. This works for a period of time but eventually the pond freezes over.
2) I have placed a “Thermo Pond 3.0 De-Icer ” (100 watts and 3-4 years old) and it does not keep a whole in the ice.  I am not sure if it is broken or not robust enough to keep a whole open based on the size of my pond
3) Placing a 50 gph pump in the pond in an attempt to keep the water moving. This works for a period of time but eventually an ice dome forms over the pump thus enclosing the pond.

Do you have any recommendations for a different approach or a better de-icer?”


You are on the right track but some of your equipment is a little under-powered. See our Winterizing Kit.

1. You have an approximate 1400 gallon pond. You should probably go with at least a  1250 or  Aquascape 1500 watt de-icer for your zone and size of pond (see attached chart). The 100 watt de-icer you have  is too small.

2.  Your pump is way too wimpy too. We usually recommend the AquaForce 1000 to be placed at an angle tilted sideways breaking the surface of the water to help keep a hole in the ice. A 50 gph pump is way too small to be effective in a climate like yours.

3.  As a final measure to make sure the hole stays in the ice, we recommend an Aquascape 4-stone aerator which also provides oxygen for the fish.

And please remember if you hammer at the ice with an ax or shovel, you risk killing the fish with the shockwaves!

General Winterizing Tips

Preparing Your Garden Pond for Winter

Although the real cold weather is a few weeks away, pond owners need to turn their thoughts to winterizing their ponds. Fall is the time of the year when your soon-to-be dormant fish build up fat reserves for their semi-hibernation over the winter. Ponds that contain fish have to be readied for the winter, at the latest when the water temperatures falls below 50 degrees farenheight. In order to prepare for the cold  weather ahead, the metabolism of your fish slows down. At this point, the fish are no longer able to digest high protein fish foods. Pond owners should switch to a low protein/ high fiber food (such as a wheat germ based fall fish food) as fall approaches in order to avoid undigested food remaining in their system once the real first cold snap occurs.

Here are some other tips and steps you can take for winterizing your pond:

Plants: Cut back all aquatic plants by 3/4’s leaving tender new shoots intact. Inspect plant containers for root bound plants and plan on which plants need to be repotted in the spring. Move all hardy water lilies and lotus to the deeper section of the pond. Some marginal aquatic plants, like cattails, iris and pickerel rush can be left on your plant shelf. Move tropical plants indoors. Store tropical water lilies inside. Remove all water hyacinths and lettuce and discard.

Pumps: Remove the pump from the pond to avoid damaging the rubber or plastic seals in the pump. Many manufacturers recommend storing pumps in a bucket of water in a frost free area. Biological filters can remain outside, but ultraviolet lights should be cleaned and taken inside for the winter. Aim the pump at an angle so the flow breaks the surface.

Aeration: We have seen fish kills in ponds that have had only a de-icer that was able to keep a hole in the ice. In these cases the gases were still concentrated enough despite the hole in the ice to affect the fish. Using an aerator helps keeps the surface of the water unfrozen as well as provides valuable aeration for your fish.

Pond Netting: Cover your pond with a net to keep the leaves out of your pond. Leaf buildup can crate unsafe conditions for your plants and fish.

Keep a Hole in the ice: To safely keep fish in your pond throughout the winter you must keep a hole in the ice. This can be done with a pond de-icer, air bubbler or solids handling winter pump. A build up of gas under the ice can be very toxic to your fish. This gas needs to have a way to escape. Never break the ice that forms on your pond as this can be detrimental to the health of your pond fish.

Thermometer: Get a thermometer! When the POND temperature drops under 55 – 60 degrees, discontinue your normal Bacteria and enzymes and switch to Cold Water Beneficial Bacteria which will be effective to 45 degrees. At 55 degrees, discontinue feeding your fish regular fish food. They may continue to eat but they will be unable to fully digest the food which may be harmful. Switch to a Cold Water Winter/Spring Food (usually containing easily digestible Wheat Germ)
Following these steps will prepare your pond, aquatic plants and fish for the winter months ahead and make for a stress free pond opening when the weather turns warm in the spring.

Winterizing Urns: We recommend that you drain the urn, pump out the basin, and bring the pump inside. With the urn, you can either turn it upside down and put a tarp over it or bring it inside a garage or shed. Aquascape also suggests using a grill cover over the urn.

date Posted on: Sunday, February 21st, 2010 at 8:23 am
Category Pond Products, Pond Tips.
You can follow any responses to this entry through the RSS 2.0 feed.

Both comments and pings are currently closed.

4 Responses to “Winterizing the Pond”

  1. Barbara

    Fabulous response! My “kids” love the disc…keeps a nice portion non-iced over. They hang out at it and seem more active than in past winters. Tempted to toss in a few Cheerios.

    February 21st, 2010 at 1:24 pm
  2. John D

    Have you ever tried just letting the pond freeze over. Fish (and many other pond animals) do survive in natural ponds that freeze solid. I think the key is enough depth that the whole thing doesn’t freeze (I doubt that even northern Ohio freezes two-feet deep.)

    I think the real issue is keeping the oxygen level high enough. If a lot of leaves have fallen into your pond in the fall, their decomposition will grab the oxygen – making it critical to have some open water. If you’ve used a net to keep leaves from accumulating (and perhaps harvested out a lot of the organic material), it increases your survival rate.

    another factor is the number of fish (and other animals) in your space. If pushing the limits on population, winter can be tough.

    Just a thought.

    February 22nd, 2010 at 5:16 pm
  3. PondMeister

    Not a good idea to let small ponds freeze over. Some fish may survive but many are killed due to the trapped gasses. Most backyard ponders have too many fish to begin with so when the gasses are trapped under the ice, many fish will die from the gasses and lack of oxygen.
    You are absolutely correct about the decomposing leaves and debris. In nature, there is a lot more room…and oxygen… under frozen natural p[onds and lakes.

    February 24th, 2010 at 4:34 pm
  4. Semrau

    thanks fgor the share

    May 15th, 2011 at 10:36 pm