Can This Pond Be Winterized to Keep Fish Alive?

[BSquared18]

Hello,

Before I get any further in researching how to winterize our pond to keep the fish alive, I wanted to ask a very basic question: would it work in our climate with our particular pond? Below is an image of our pond, followed by some facts you need to know before giving me any advice.

First, our climate: Minneapolis, Minnesota. It doesn't get much colder anywhere in the lower 48 states. Below-zero Fahrenheit temps will occur during the winter.

Next the fish: two dozen feeder goldfish I purchased in the spring. They were about an inch and a half or so to begin and have gotten somewhat larger but nowhere near the size of Koi. A very hardy breed. Only one died (soon after entering the pond) from spring to now (early fall).

As you can see from the image, the pond is shallow. At the pond's fullest the depth varies from about 10 inches at one end to 9 inches at the other. The pond is rock and cement, professionally installed. No plastic or rubber liner.

I plan to turn the waterfall off during the winter and remove that pump.

So, my question is, will the fish survive in this pond and environment if I use a heater and/or bubbler to keep the pond from freezing all the way to the bottom?

By the way, the contractor who built the pond said to fill it with water during the winter so pressures are equalized to prevent cracks in the pond. Would using a heater or bubbler increase the chances of cracks by interfering with the pressure-equalization?

Looking forward to points of view.

Thanks,
Bill

 

[Tula]

In your climate, given the pond's depth and water volume, I'd suggest covering the pond for the winter if you plan on over wintering the fish.

We made a simple "hoop house" by securing electrical conduit to rebar driven into the ground thus making a hoop. then covered by a pool solar cover. For a smaller pond you could buy a smaller amount of plastic rather then a solar cover.

 

[GBBUDD]

no 10 inches is not deep enough . By its self the pond could freeze solid unless you cover it with a green house type idea

 

[Mgessert]

It will freeze solid. I’ve seen Minihaha Falls freeze solid in your neck of the woods.

 

[BSquared18]

Thank you for the information. Does anyone have a link to a video showing the green house mentioned? The pond is shaded by some trees and shrubs (although, of course, the shrubs and some of the trees would have lost their leaves). Would that shading cause a problem with the green house approach? And, of course, the sun is very low and weak, even at noon, during that time of the year.

As an alternative, I've considered putting the fish in a large rubber or plastic tank in our tuck-under garage, with a bubbler to keep the water moving. The area would be much smaller than that of the pond; however I suppose it wouldn't be much deeper than the pond. I could also have a small, aquarium-type heater to warm the water in the tank, if it is felt that would be necessary. The garage isn't heated most of the time but would be when we are working in it. Would that be a problem? Maybe turn off the tank heater, if there is one, when the garage is heated?

Bill

 

[GBBUDD]

if they go to a tank in the garage and you heat or just keep the temps from getting cold the fish will be more active. thus requiring a filter not just air. now that could be a simple as a charcoal bubble filter or two cleaned often.

a green house can be as simple as placing 2x across the pond and then lay a tarp over it. keep in mind the weight of snow and how to direct that off of the area.
or you can set up and host of configurations.

but anyway you slice it 10'' is realy to shallow imo

 

[Mgessert]

I think a tank in the garage with aeration, kept just at or above freezing, and don’t feed, might work. I would just try to overwinter three or four fish though.

 

[BSquared18]

I really need this input since I sometimes tend to be overly optimistic that something will work.

That being said, back to the idea of covering the pond. Below is an image of a frame with metal screening on it. I built it to keep raccoons from eating our hyacinths. (That's another story.) You can see the metal rods under the screen for additional support. Would that setup with a tarp over it work well enough to reduce freezing?

Am I correct that I'd also want to have one, two, or more bubblers to keep the water moving?

In addition, I'd go out after every snowfall and remove the snow by lifting the tarp (two of us, one on each end) and then replacing it.

Mgessert: I know what you mean; I've seen those frozen falls too. Do you feel that the setup I describe would not be enough to protect against total freezing? I have to admit, I'm not totally sure myself.

Over,
Bill

 

[WaterGardener]

There are lots of ideas for winter pond covers online. Just Google it.

But at the depth of that pond, I think the fish would be safer indoors. They would also need some light and that can be a shop light hanging over the tank with full spectrum bulbs in it.

Stock tanks work well for winter housing or small temporary pools will work. Those both come in various sizes so one could likely fit the space you have.

 

[BSquared18]

Re: "...I think the fish would be safer indoors." On that note, I'm reminded that a few years ago I took some bullfrogs that I had raised from tadpoles in the pond and wintered them in a large (maybe 31 gallon) Rubbermaid container with a bubbler. It was great in the spring to see the frogs poke their noses out of the water. My memory is that only a thin layer of ice formed, which I periodically, if memory serves me, broke up.

Indoors would certainly eliminate a lot of fuss. Of course, we're dealing with a couple dozen (small) fish, not six or so frogs.

Given how many fish, does anyone have a suggestion for how many gallons large the container needs to be? The smaller the better would work in our garage.

By the way, why is a light needed?

Bill

 

[Mgessert]

I agree with WaterGardner, it’s just too shallow to keep open in your climate, even if covered, unless you’re thinking heated greenhouse. Your pond in the summer will probably support five to ten adult goldfish, so I’d give away the rest and just overwinter those, maybe in a portable child’s swimming pool. I would also test water quality daily for a while, then weekly, in case ammonia builds up. If you wait until it gets really cold before you bring them in, you won’t have to feed them and it will only be for six months or so (just kidding). I’m from Green Bay, WI and now live in FL so have successfully avoided this particular problem.

 

[BSquared18]

Helpful, Mgessert, although "pond in the summer will probably support five to ten adult goldfish" remains to be seen, since two dozen feeder goldfish have had no problem. Of course the feeders are small, and I assume you're saying they will eventually get a lot bigger.

Thanks everyone for showing me the error of my ways when I considered keeping the fish in the pond over the winter. We'll either keep them in the garage or find a home for them. Have done the latter in the past without any problem.

If, as Mgessert suggests, the fish will get too big for the pond, we would elect to get new ones each spring, because the smaller ones fit just right in that pond, and we love to see a couple dozen schooling. Cost wise, about ten dollars for two dozen fish is a bargain.

Bill

 

[poconojoe]

9"-10" is pretty shallow. I'm guessing the fish should be brought inside.
It's 2 dozen small feeder goldfish, right?
Couldn't you setup a regular fish aquarium inside the warm house? If you don't want one big aquarium, how about two? Maybe two 50 gallon tanks? They aren't too expensive.

If you keep them outside and go with the greenhouse approach, maybe use heavy clear plastic sheeting instead of a tarp. The clear sheeting will allow the sunlight to pass through.

 

[GBBUDD]

2 dozen feeders that's what we are talking about? i 55 gallon is all you need with a foam filter do 25 % water change weekly and they will be fine

 

[BSquared18]

I appreciate every ones help. You helped me see that our pond is too shallow for wintering the fish. Since we cannot winter the fish in the pond, we've decided to do what we've done previously, which is to go on Nextdoor and find a home for the fish. Next spring, we'll stock the pond with a couple dozen new fish. We've done that successfully before. That way, we get small fish that fit nicely in the pond. For us, it's the only decision that makes sense.

Bill