Bought a new house with an old pond....

[rellascout]

I recently bought a house with a Koi Pond. I have had a pond before which I designed and built but had to fill it in when I moved. I have not had a pond in about 8 years. The new pond looks like this. It has a lower pond which is feed from a in pond pump up which feeds into a bog pond which then feeds the waterfall. The bog is obscured in this pic by the juniper bushes. I estimate that it is only a 1.5 ft to 2 feet deep. It is doing an excellent job filtering the pond. The pond is over 15 years old and the liner in the stream is showing its age. It is at the point where it either needs to be relined or it need to be shuttered.

It has some large fish in it. Fish range from 1.5', the largest one, and about 4 others 1' with a few smaller fish here and there. The largest fish has been in there for over 15 years. It is a nice looking looking Sanke. Not show quality but a beautiful backyard fish.

So the questions it what to do. To reline the pond will require me to remove a lot of the stone work around the pond which is held in by concrete. I would have to redo the stream and the bog. The pond does not have a bottom drain so that would have to be installed. I do not have the exact dimension of the pond but I would guess the it is 10' X 8' and the bottom slopes from 1.5' to 3'. The stream is over 50'. The bog is 6'x8' and 2' ft deep. So I calculate over $550 with shipping for EPDM liner.

From there bottom drains and new external pump system, like a Sequence 4000 with a large priming pot, replacing the in pond pump system I figure another $1000. I don't see a need to change the filtering system because the bog is more than sustaining the pond system as it is.

So the real issue I see is the time it will take me to remove the slate some of which is concreted together, drain the pond, remove the debris, install the new bottoms drains, reline the pond, bog and stream. I do not know how to store the koi while I tear it down and rebuild the pond. Having a large enough active working bio filter that can sustain the large fish load for 1 week to 2 weeks is above my current level of knowledge. So I am looking for thoughts. I would feel horrible if the koi died. I would rather sell the koi and have no pond then try to do the relining and have them die.

Thoughts?

 

[Tula]

I've seen people use those large Intex swimming pool to house their koi, while redoing their pond. I've also seen some shower filters, that just sit inside the pool. Is there any biological media from the bog or pond, you could use to make a simple shower filter? I'd also add good aeration to the pool.

 

[rellascout]

Yeah makes sense. I could get one of those pools seed a filter with bio media from the bog and then add some aerators and basic filters to maintain them for a few weeks.

 

[addy1]

If just the stream liner is showing age, most likely more exposed to the elements, can you replace just it?
The pond looks great btw
I use a bog filter, never need to do anything to my pond except groom lilies.

 

[Lisak1]

Your pond is lovely! Your years of pond knowledge will serve you well!

So first question - you say the liner is "showing it's age" but is it actually causing any problems? If not, I would leave it be. If it's just the stream, could you just add a new layer of liner over the existing liner? Much less complicated, way lower cost, and probably less than a day's worth of work.

Question numberr two - why add a bottom drain? You're just adding cost and complication to a system that clearly works well without it.

Just some food for thought!

 

[rellascout]

Your pond is lovely! Your years of pond knowledge will serve you well!

So first question - you say the liner is "showing it's age" but is it actually causing any problems? If not, I would leave it be. If it's just the stream, could you just add a new layer of liner over the existing liner? Much less complicated, way lower cost, and probably less than a day's worth of work.

Question numberr two - why add a bottom drain? You're just adding cost and complication to a system that clearly works well without it.

Just some food for thought!

The stream is leaking some water and is showing rips and tears on the spots where it is exposed. The previous owner inherited the pond from the original owner and did not do a great job of keeping the liner covered and UV and light exposure has taken its toll. My initial concern was that the main pond liner would have similar issues but the more I think about it that liner is much more protected than the exposed areas.

I was going to put the bottom drains in to help with cleaning and maintenance but only if I was going to do a complete relining. In my original pond I did not install them and always regretted it afterwards but you are right the system has worked for 15+ years there is no need to change it. I do think I am going to get a better more efficient pump. The one that is in there is a Lowes special which works but is horribly inefficient.

The more I think about it I am just going to redo the stream which I can get done in a day or 2 at the most. This will allow me to keep the aesthetic and not have to move the fish. Keep the thoughts coming.

 

[Lisak1]

OK - so the stream should be an easy fix... well, easy for me to say, right? Ha! There's a lot of stone there - is it just laid in, or does it involve mortar? If I were going to redo that stream, I would work it a bit different. Right now it resembles a concourse. You could add a bit of interest by building in some small pools and a few narrows to change the water flow a bit as it comes down the hill. A few well placed boulders or even working some wood into the design would really add to the appeal. It appears you have plenty of depth to work with in the original design.

If you really wanted to tweak the look, you could remove the flat stone from the point at which is starts being stacked and replace with more natural looking boulders and then continue that look up the hill. It would blend nicely with your patio.

I'm really good at planning work for other people - haha!

Two ponds to look at here - @addy1 has a beautiful, long stream on a hillside with lots of twists and pools and @RobAmy have a flatter landscape with a beautiful, natural looking stream. A little inspiration for you!

 

[carolinaguy]

Would you consider converting the stream to a concrete base? There are methods of waterproofing the concrete. One is xypex. Another is mixing S40 with thinset mortar. The concrete can be colored with concrete dye. Just a suggestion.

 

[Waterbug]

My two cents and unfortunately diametrically opposed to most in this forum, but I'll give it a try. The upper bog (gravel I assume) is not really doing anything filter wise. The 50' stream is the work horse. It is basically a Trickle Tower or Shower filter which have been tested against bog/gravel filters and other submerged filter media and shown to be in the ballpark of 10x better. It's all about O2 getting to the bacteria and keep the bacteria clean. When you remove the gravel you will understand completely...it will be disgusting and full of muck.

Bog aside...logistics wise: I suggest bypassing the bog so water from the pump goes into the stream, or even bypassing the stream too. So you'd just have the bottom pond with the fish. Test ammonia levels, know the difference between ammonia (NH3) and ammonium (NH4) which can reduce freaking out and dumping lots of chemicals into the pond when none or needed. Understand and be ready for water changes if needed and/or check out 24/7 trickle water changes. My guess is you'll have no ammonia issues, but it is possible.

That will allow you to dig out the bog and replace the liner. When ready you can pump water from the lower pond to the upper again. That will help you net fish too. Buy a proper Koi net for catching if needed. Move the fish to the upper along with the pump. Monitor ammonia.

Redo the stream and lower pond. Add water to the lower and wait for chlorine level, if any, to become safe. Takes a day or so, couple of weeks if you're nervous. For sure when water starts to green up chlorine level is safe. You can then move the pump to lower, or turn on a new pump and so water moves from lower to upper and down stream. At this point to want to net the upper pond to keep the Koi from jumping. or just check the pond to see if any jumped out. New water can make Koi jump. I'd block the Koi from getting into the stream as that is their normal ancestral behavior.

Now the fish can be moved to the lower pond and you're done.

Removing the slate is likely to be much, much (maybe 3 muches) easier than you think.

Bottom drains...another diametrically opposed topic in this forum...but here goes. A bottom drain by itself isn't very useful. Bottom drains are part of a bigger system. To work well you really need jets of water to push debris to the drain. These are called Tangential-Pond-Returns (TPR). And then you need a filter to remove the captured debris which today is normally a sieve filter. This is all expensive and completely not needed for your type of pond. Your fish have been fine without one. And you have lilies, the water movement needed for a bottom drain would likely tangle up and push the leaves around.

All depends on the type of pond you want.

To install a tradition bottom drain (there are options but not as good) means removing the current liner and digging a trench for the pipe (can lay pipe on top and concrete) to the sieve, building a box for the sieve...this is all a big deal and you you gain very little, if anything. Instead I suggest cleaning out the pond and laying the new liner right over the current and no bottom drain. Easy. Use a vacuum if you like to keep the pond clean. You will spend a tiny fraction of the time over the life of the pond compared to the work installing a drain system.

If you do plan to add a bog/gravel "filter" to the new pond a bottom drain really gets you nothing as far as fish health goes. Bogs act as settling chambers, really excellent settling chambers. Debris collects and rots there, inside the pond. It doesn't matter one bit whether it rots inside a bog or on the bottom of a pond. Consider putting lilies in the upper pond maybe. Again, when you remove the gravel you will learn this in a way that will leave no doubt..

 

[addy1]

Here is a down view of the stream and a up view. It is around 85 feet long heading down the slope. Switchbacks. A straight stream bed would have been unnatural looking. I run it on a timer, a separate pump due to the head pressure sending the water up the hill and on to the deck for the deck ponds.

Two ponds to look at here - @addy1 has a beautiful, long stream on a hillside with lots of twists and pools and @RobAmy have a flatter landscape with a beautiful, natural looking stream. A little inspiration for you!

 

[rellascout]

Good info Waterbug. Honestly I am not sure what is in the bottom of the bog. We just moved in and got a cold front in so getting my hands and arms into the pond will have to wait for a bit. Interesting take on the bog filter. If my memory serves me correctly I agree that the stream is playing a huge roll in the filtration of the pond.

I am familiar with proper water chemistry and will pick up a good testing kit and will monitor the water. I am not in a position to debate the value of the bog but at this point I am very much in the if it ain't broke don't fit it. The previous owner had very little knowledge of ponding or fish maintenance. Even being aways from ponding for over 8 years I know more then he does. It is a testimony to "bullet proof" nature of the design.

There is a fair amount of vegetation growing in the upper bog. Tons of parrot feather, reeds, rushes and other yet to be identified plants. I am going to wait for it to warm up before I really start to get into it and see what is in there. I would guess from my conversations with the previous owner a bit of a cleanout is due.

I am not looking to reinvent the wheel just looking to make the stream water tight and maintain the setup while keeping the fish alive. The main pond is fairly clean. I appears that they at least removed the major debris prior to the winterizing of the pond. I will again wait for it to warm up before I get in there and give it a good spring cleaning.

I guess I was sort of getting ahead of myself a bit and after thinking about it more I believe that redoing the stream is the place to start. From there I can do the bog if I need to and then tackle the main pond again if needed. I will look to do it in stages if at all possible.

 

[rellascout]

Addy1 nice looking stream setup. I just eye balled the length of the stream I will have to get some string out and actually measure it. Might be less than 50' but I would bet 50' is close and if I replace the liner on that portion I will have to account for the folds for the turns and the bends.

LisaK1 I like the ides of a different rock setup on the stream. I think that it wold look more natural and also allow for better coverage on the stream bed liner but for the lower portion of the pond I think I am going to leave it as it is again going with the if it ain't broke don't fix it mentality.

In the next few weeks I should be able to determine where I am leaking water from the stream. I am hoping that it is minor and that I can patch it for now buying myself sometime to formulate a longer term plan to redo the stream, then the bog and then the main pond using basically the same design with some updates and tweaks.