Newbie questions - koi garden pond

[PondWish]

Hello! I inherited a pond at my last house, which was 50 years old and a maintenance mess, but enough to get me addicted to it. Now, I’m looking to build a koi garden pond at the new place. I’ve read through a lot of the go-to tips for construction and newbie questions, but I still have some left as I start my planning (and I’m sure I’ll have another round soon enough). Please feel free to make recommendations as well.

Basic specs:
Goals:
- Home for at least 20 non-jumbo Koi (pedigree doesn’t interest me, so realistically I may get a couple fancy ones some day, but I best most will be American bred Koi that won’t grow larger than 20”)
- space for lotuses (in baskets)
- bio-filtration with extra for backup if needed

Pond:
- irregular kidney shape
- ~18’ long x 11’ wide
- max depth of 4’ desired, at least 3’ (freeze line is at 15” for my area)
- 2 shelves, one at 1’ and one at 2.5’, averaging 1ft deep
- shelves lined with boulders and then pea gravel
- pipe layer along shelves to pull extra gunk away and to rinse out when needed
- Skimmer and pump sit on the south wall

Bog:
- 11’ x 7’ OR 16’ x 4’ (haven’t decided)
- 1’ deep (although likely keep waterline to 8” deep)
- fed from below via the main pump
- sits on the north end

Waterfall area
- Whatever I can safely fit in a 15’x15’ liner
- hopeful large spillway rock and at least 2 different fall sections that connect and then part

No stream

Equipment - this is where I have all the questions:
- A 5-6,000 gph external pond pump should be plenty? Should I plan on a second one from the pipes along the shelves or can they just feed into the skimmer area?
- Do I need extra filtration to start, or can this be added in later based on the performance of the bog/shelf?
- I do plan on a bottom drain, do I need an air diffuser? Should I get one anyway since it’s hard to change later?
- How do I calculate stone needs? I’ve seen several formulas, but it honestly never seems like it’d be enough.
- Has anyone successfully built a pond themselves, but then had a landscaping company come in to place a few large boulders that otherwise couldn’t be managed? If so, any tips for this?

Main question - Besides getting a good liner, what is worth splurging on and what can be upgraded later as desired?

Thank you and I appreciate you!

 

[hamstermann]

I don't have a lot of answers for you, but I can tell you that the larger your bog is, the longer it will be til you have to clean it, if at all. @addy1 has a great one that she's never had to clean and it's over 10 years old now.

I'm interested to hear more about the pipe layer on the shelves. Do you just mean like an undergravel filter to suck stuff into the gravel, and maybe eventually to your bog? And you'd reverse the flow to rinse out?

 

[PondWish]

I don't have a lot of answers for you, but I can tell you that the larger your bog is, the longer it will be til you have to clean it, if at all. @addy1 has a great one that she's never had to clean and it's over 10 years old now.

I'm interested to hear more about the pipe layer on the shelves. Do you just mean like an undergravel filter to suck stuff into the gravel, and maybe eventually to your bog? And you'd reverse the flow to rinse out?

Thank you, I have read through addy’s post and gained lots of good tips. But I almost feel like your always waiting for someone to say the one thing you haven’t heard yet that some how changes your mind completely on what is needed.

I got stuck in a dedicated koi pond discussion group for a while and they were intense to say the least; very against any garden with koi. So, that combined with my previous maintenance nightmare pond has me a bit extra afraid about my needs to ensure stable water quality and low annual maintenance.

Yup! That’s exactly what I mean. I can’t decide if I’d need another small pump to handle it, but the idea would be to prevent stagnation and build up in the shelves. I know this can be done with aeration as well, but I haven’t found what I feel is an optimal solution for them w/ being so long and skinny.

 

[j.w]

@PondWish
I only have goldfish so not much help w/koi. One thing tho is I didn't know koi came in different full growth sizes? I just looked it up and looks like the Japanese varieties reach about 26" and other jumbo ones can get 36" or ? So I learned something today

 

[PondWish]

View attachment 161195@PondWish
I only have goldfish so not much help w/koi. One thing tho is I didn't know koi came in different full growth sizes? I just looked it up and looks like the Japanese varieties reach about 26" and other jumbo ones can get 36" or ? So I learned something today

!

I love Koi. I just want pretty ish-fish with a variety of markings; size is really not important. The jumbo ones scare me, tbh. Lol.

Goldfish are pretty too! Eventually I hope to have a small bubble rock pond in front of the house and think I may have to learn more about goldfish come that day.

 

[hamstermann]

Thank you, I have read through addy’s post and gained lots of good tips. But I almost feel like your always waiting for someone to say the one thing you haven’t heard yet that some how changes your mind completely on what is needed.

I know that feeling exactly!

I can’t decide if I’d need another small pump to handle it, but the idea would be to prevent stagnation and build up in the shelves. I know this can be done with aeration as well, but I haven’t found what I feel is an optimal solution for them w/ being so long and skinny.

I'd go with jets instead because you'd get a stronger stream, it wouldn't need to be blown out because they only flow one way, and you can control flow in the pond through them - just aim them so they shoot up and toward the intake bay/skimmer/zero edge. Anything that might try to sink gets lifted and pushed to one central place, making it easier to clean up.

Modern design aquascaping has a good YouTube video on it:

And so does OzPonds:

 

[j.w]

!

I love Koi. I just want pretty ish-fish with a variety of markings; size is really not important. The jumbo ones scare me, tbh. Lol.

Goldfish are pretty too! Eventually I hope to have a small bubble rock pond in front of the house and think I may have to learn more about goldfish come that day.

Have you ever seen Shubunkin goldfish? They to me look like mini koi due to their various colors and patterns. Some of them have long flowing fins too and they stay under I'd say 12". Take a look online and see a bunch of different ones.

 

[GBBUDD]

Welcome to the group,

Yes dedicated koi keepers can certainly be a bit brazen with there's is the only way . they call my pond a pretty toilet . i call there's a prison cell . I was told by an old timer when i was coming up in the building trades that there is 10 was to accomplish the same task , each having its own merits advantages an disadvantages, NOT ONE IS RIGHT FOR ALL AND YET THERE REALY IN NO WRONG EITHER JUST will require a lot more work to maintain

 

[addy1]

Welcome to the forum!

I have shubunkins, no koi. I wanted pond plants , lilies, and didn't want to deal with koi.

 

[GBBUDD]

6 YEARS AGO I WAS THE NOB asking questions making the forum's eyes roll with my dumb questions. now i m
still making the eyes roll but with my dumb answers

 

[PondWish]

I'd go with jets instead because you'd get a stronger stream, it wouldn't need to be blown out because they only flow one way, and you can control flow in the pond through them…

Thank you, I’ll look into it!

 

[PondWish]

Welcome to the group,

Yes dedicated koi keepers can certainly be a bit brazen with there's is the only way . they call my pond a pretty toilet . i call there's a prison cell . I was told by an old timer when i was coming up in the building trades that there is 10 was to accomplish the same task , each having its own merits advantages an disadvantages, NOT ONE IS RIGHT FOR ALL AND YET THERE REALY IN NO WRONG EITHER JUST will require a lot more work to maintain

Thank you! I’ve been looking through your work for a while now and it is very impressive! I hope to end up with a similar style to what you’ve built (but smaller ).

 

[PondWish]

Welcome to the forum!

I have shubunkins, no koi. I wanted pond plants , lilies, and didn't want to deal with koi.

Hi, thank you! I know, I want Loutuses and Koi together for some silly reason and already know I’m destined for some ruined plants until I figure out a good way to have them both.

 

[GBBUDD]

Thank you! I’ve been looking through your work for a while now and it is very impressive! I hope to end up with a similar style to what you’ve built (but smaller ).

Yet to meet the foolish idea in someone's mind to go larger as I'm vacuuming and netting leaves. See not only was I soft for building a large pond but I also put it where it's surrounded by giant maples

 

[GBBUDD]

Hi, thank you! I know, I want Loutuses and Koi together for some silly reason and already know I’m destined for some ruined plants until I figure out a good way to have them both.

It's not as hard as you think . In my last video I showed two large boulders. And how they are sitting on a large shelf. The two boulders which normally you would expect to have being the edge of the pond are actually surrounded by water. Though in my video it's all plants that you can see they have hidden the water. The point is to make a stone wall between your koi and your lotus. On the koi cant get past . Problem solved you'll probably make a nursery for baby koi in doing so which could realy be an interesting area. "So much for smaller "