How deep is your pond and how deep would you suggest?

[Ynott116]

I'm located in the Cleveland Ohio area and I'm looking to make a below-ground and above ground pond for my koi. My plans for this pond our 10' by 6' wide And I'm hoping to dig down 3 ft and do 1' above ground. I just want to know if that would be deep enough to be able to house my koi in during the winter. It does get pretty cold in Ohio typically in the '30s and sometimes the teens. Please let me know your feedback because if I could dig 2 ft down instead of three that would be a little more ideal but I want to do what's right for the fish obviously. Thank you

 

[Mgessert]

How many koi do you have? That will determine how many gallons your pond needs to be.

 

[Ynott116]

I have 12 koi at the moment but I'm looking to keep 5 to 7 koi long term, in this out door pond.

 

[GBBUDD]

3 foot is what i feel is minimum in cold weather areas but we have seen some that are only 2 feet deep. if a foot is above grade it will chill the water far more than is below grade

 

[mrsclem]

I would go larger if possible. With those measurements you are at about 1750 gallons. Ok for 2-3 full grown koi.

 

[Ynott116]

3 foot is what i feel is minimum in cold weather areas but we have seen some that are only 2 feet deep. if a foot is above grade it will chill the water far more than is below gra

3 foot is what i feel is minimum in cold weather areas but we have seen some that are only 2 feet deep. if a foot is above grade it will chill the water far more than is below grade

Okay thank you for your feedback 3 ft is ideal for me but we'll see how the digging goes I guess lol also I was going to insulate the walls before I put the pond liner down do you think that would make any difference during the winter on the above part? Maybe it will maybe it won't I guess.

 

[Ynott116]

I would go larger if possible. With those measurements you are at about 1750 gallons. Ok for 2-3 full grown koi.

Two to three full size koi still won't be disappointing to me haha And I believe it's best for any fish but what's with all these koi ponds that are maybe 12 ft by 12 ft with it seems like 25 or more in them.

 

[Ynott116]

Another question what size bottom drain would you recommend? Sorry if I'm asking beginner annoying questions but that's who I am this week.

 

[GBBUDD]

Okay thank you for your feedback 3 ft is ideal for me but we'll see how the digging goes I guess lol also I was going to insulate the walls before I put the pond liner down do you think that would make any difference during the winter on the above part? Maybe it will maybe it won't I guess.

it will help sure, how much most sheet foam has minimal r values but there's no harm in it. just don't use the white little ball stuff termites love to build there homes in it.

 

[GBBUDD]

Another question what size bottom drain would you recommend? Sorry if I'm asking beginner annoying questions but that's who I am this week.

pipe size minimum of 3 inch and there should be two on the same pipe so no one can get stuck to the drain and held underwater. it's a code thing look it up for your area.

 

[Jhn]

Two to three full size koi still won't be disappointing to me haha And I believe it's best for any fish but what's with all these koi ponds that are maybe 12 ft by 12 ft with it seems like 25 or more in them.

Have you seen those ponds in person and for a length of time. Eventually those ponds will fail, as the koi will overwhelm the system. The pluses and negatives of the internet, so much info at your finger tips, but you need to parse through it as any idiot can put info on it and say it is factual. Define successfully keeping a koi pond, as well, is it a couple years or is it for the life of the denizens of the pond, for most it is the latter.

As for your depth, if you are going 3’ down and 1’ up that is more than deep enough for your area, even though 1’ is above ground, imo the chilling of the water will be minimal during winter time. I have fish make it in above ground tubs with nothing but a pond breather keeping them alive, I am in a slightly warmer zone, but go through similar winters with temps in the teens or the single digits.

 

[WaterGardener]

First rule of building a pond -- Make it bigger.

Second rule -- Dig it deeper.

You won't regret having it larger and deeper. You might regret that it isn't.

 

[Lisak1]

I would add one caveat about the "deeper" part - for me it was important that I could safely get in the pond and work and that I could reach the bottom with a net to clean out debris. Any deeper than three feet would have made that a challenge. Water volume is important though so I would suggest larger rather than keep going deeper. Increased size also gives you something else that's critical - increased surface area which leads to the next point.

I've seen dozens and dozens of ponds in the Chicago area - much colder than your winters and for much longer periods of time - that are 24 inches deep and house fish all winter long. HOWEVER - the total volume of the water, the surface area of the pond and the biomass of the fish are all important components as well when you are keeping fish in a pond covered with ice for weeks at a time. Goldfish will do fine in a pond that would be deadly to koi in the same pond for example.

As for those that keep an insane number of fish in a small pond - they have an insane amount of filtration on that pond. Filtration that they monitor and clean constantly. If your goal is a DKP (dedicated koi pond) then you'll have a whole lot of research to do on the type of filtration needed for a pond of that type, which is more a swimming pool for koi. Not the same as what most have here - eco style garden ponds.

 

[jgrandmont]

Also keep in mind that you're only going to get that max volume (@mrsclem calculated 1750 gal) if the sides are perfectly vertical. If the sides are sloping and/or you have any step-ups or shelves for plants, that's going to reduce the volume. I have a similar-sized pond that I calculate at only 700 gallons because of this.

 

[j.w]

@Ynott116 make your pond as big as possible, the bigger the better and digging is good for you health