How deep is your pond?

[Lisak1]

Get a cold enough snap, and it'll freeze deeper and deeper.

We've experienced two polar vortexes in Chicago since our pond was built in 2012. I'd say that qualifies as a cold snap. The ice was no thicker than it was in a "normal" winter here. We do keep our pond running all winter which probably has some impact on that, but the idea that ice will just keep freezing deeper and deeper when it suddenly gets cold - or stays cold over a prolonged period - has never proven to be true in our pond. Some years the ice is thicker, but it's never gotten more than four inches thick in even the coldest year. I've heard that having an ice cap can actually help keep the water warmer under the ice than if it's open water. Same is true with snow cover.

And the frost line in my area is 36 inches deep, for reference.

 

[brokensword]

We've experienced two polar vortexes in Chicago since our pond was built in 2012. I'd say that qualifies as a cold snap. The ice was no thicker than it was in a "normal" winter here. We do keep our pond running all winter which probably has some impact on that, but the idea that ice will just keep freezing deeper and deeper when it suddenly gets cold - or stays cold over a prolonged period - has never proven to be true in our pond. Some years the ice is thicker, but it's never gotten more than four inches thick in even the coldest year. I've heard that having an ice cap can actually help keep the water warmer under the ice than if it's open water. Same is true with snow cover.

And the frost line in my area is 36 inches deep, for reference.

Lisa; I'm in agreement with most of your post, but will note that it's not a 'cold snap' that causes thick ice; it's prolonged periods of sub-freezing temps. Ice builds slowly after initial set up because now the water below is being insulted from the sub freezing air. The longer this goes on unabated, including cloud-cover with no sun, the thicker it gets. Our frost level here where I live in SE Mich is 42". I've played pond hockey my whole life and can tell you here, we can get 14" of ice easy, during the above mentioned times. That said, I don't think in the years prior to my winter pond tent, I ever got more than 10" and that's a guess during early spring.

You're correct re insulation of ice and snow, though there is a downside; with less light getting through, the algae below dies and this adds to the toxic gas build, especially without any breakage of the surface during these same thick snow/ice days. There is some benefit to actually shoveling off a portion of an iced up fish pond, just to let the light penetrate.

And I think most ponds/lakes require at least 4" to hold a person safely ( 8" - 12" for a vehicle, but I forget exactly).

I think the idea here though is deeper IS better in many ways, not just winterizing. And without at least 10' - 13' of depth, the water temp in a shallow pond will be the same as a deep one, all else being equal. A deeper pond will give more of the earth's natural temp (45-50 F) to the water and help keep the temp warmer. A shallow one won't get that benefit, so there is value to 'deeper is better' even if succes CAN be had with shallower.

Just some thoughts.

 

[Faebinder]

I'm all about build your pond big enough for the fish you intend to keep. 100% my mantra. However, I'd be willing to bet that most fish that get taken from a pond are snatched at the surface, not the bottom. Depth makes no difference if they voluntarily come to the top. And any predator that can go two feet deep after fish can go three feet or four feet or five feet.

There are many reasons why people don't want to go deeper than 2 feet - kids, pets, too hard to dig, local ordinances, etc - and the constant "ponds have to be deeper than 3 feet for koi" can be really discouraging. Honestly I think most garden pondkeepers are better off sticking with goldfish, but if you can build the volume but don't want to (or can't) go deeper, koi will do just fine.


I don't know many people who are building with the idea of enjoying their ponds for 100 years, though. Would you say a 30 year old koi is fully grown?

Here is a link to a chart. https://www.google.com/url?sa=i&url...ved=0CAkQjRxqFwoTCJif2uzLpPMCFQAAAAAdAAAAABAI

The increase in length is minor but ongoing over the years as they get older. Plus they also increase in weight - girth.

 

[Faebinder]

Look at this chart. Check the length from year 22 to year 97 and tell me did the koi grow by 20 cm or not?

 

[PH Number 9]

20 feet by 15 feet with a shelf 3 feet x 15 feet at 18" running down to 39" deep before rising to 23" at the opposite side.

 

[Mr. Green Frog]

We've experienced two polar vortexes in Chicago since our pond was built in 2012. I'd say that qualifies as a cold snap. The ice was no thicker than it was in a "normal" winter here. We do keep our pond running all winter which probably has some impact on that, but the idea that ice will just keep freezing deeper and deeper when it suddenly gets cold - or stays cold over a prolonged period - has never proven to be true in our pond. Some years the ice is thicker, but it's never gotten more than four inches thick in even the coldest year. I've heard that having an ice cap can actually help keep the water warmer under the ice than if it's open water. Same is true with snow cover.

And the frost line in my area is 36 inches deep, for reference.

Here's a reference I was looking at when responding before which explains how quickly and thick ice can form:

Freezing formula

Winter brings new opportunities to experience the outdoors. Take a look at the activities that go on during a cold and snowy day. Many kids and even some energetic adults venture outside to sled, b…

www.columbiatribune.com

"Cold snap" on my end was referring to https://en.wikipedia.org/wiki/Cold_wave which can usher in rapid ice.

 

[Jhn]

My ponds are around 4’ or so. Would agree deeper is necessary if pond Is being shut down, for the winter. If you are leaving the pumps Running using a deicer, pond breather, air pump to keep the pond open, a 3’ depth isn’t go8ng to matter as much. There are ways to keep your pond from freezing hard.

Habe had fish make it through in an above ground tub that is 2’ deep with nothing but a pond breather and over a foot of ice.

 

[GBBUDD]

I use a large nitto 120 with two twelve inch blade's to keep the ice open in one spot and on the coldest of spells it has frozen over Briefly . usually accompanied by snow fall but the next day it is usually open again. Most areas that get crazy thick layers of ice also get some good snows and that's when you can get some inches of ice as the snow will absorb moisture and ice up on it's own creating the thick layers of ice. that's why most areas in the first of winter you get the ice you can see through and watch the fish . then a snow fall and the ice clouds up

 

[Lisak1]

but will note that it's not a 'cold snap' that causes thick ice;

Not my term... just responding to @Mr. Green Frog .

I'm sure our ice experience is heavily influenced by moving water - we don't shut the pond down and have water that's stored six feet underground. The constant influx of "warmed" water probably helps.

I will stick by my original claim though that koi do find in 24 inch deep ponds in Zone 5. I've seen it with my own eyes, which is all the convincing I need. Are there exceptions? Sure. Every pond is unique in 100 different ways, which leaves the door open for all kinds of things happening. But I'm pretty confident that the pros would build them deeper if they learned from experience that it was a problem.

 

[Faebinder]

Not my term... just responding to @Mr. Green Frog .

I'm sure our ice experience is heavily influenced by moving water - we don't shut the pond down and have water that's stored six feet underground. The constant influx of "warmed" water probably helps.

I will stick by my original claim though that koi do find in 24 inch deep ponds in Zone 5. I've seen it with my own eyes, which is all the convincing I need. Are there exceptions? Sure. Every pond is unique in 100 different ways, which leaves the door open for all kinds of things happening. But I'm pretty confident that the pros would build them deeper if they learned from experience that it was a problem.

I am sure they can survive in 24 inches.. I just highly recommend against this long term. The average size of a koi when they are fully grown is around 3.28 feet. 24 inches is only 2 feet. A full grown koi can never really swim at an up or down angle at some point in that 2 feet pond. It's sorta like us living in houses with 6-7 feet ceilings.

 

[brokensword]

I am sure they can survive in 24 inches.. I just highly recommend against this long term. The average size of a koi when they are fully grown is around 3.28 feet. 24 inches is only 2 feet. A full grown koi can never really swim at an up or down angle at some point in that 2 feet pond. It's sorta like us living in houses with 6-7 feet ceilings.

Average? I don't see that when I google; comes up at 20-26", which has been my experience. Now, if you mean can reach that length...no problem. But 40" average? Must be a lot of large ones to even get an average to that number.

 

[GBBUDD]

Koi are river fish there's not much up and down swimming. Though I do have a 6 foot deep end and the fish love t o dive