HELP PLEASE

[Markaw]

I have recently bought a property here in not so sunny Worcestershire, that includes a pond; I had one at our old house but by most pond people’s standards it was a green puddle! My new one is on another level and although there is so much information available on the web it is a minefield of conflicting and contradictory ideas.

My new pond (see attached pdf [I hope you can see all the info on there]) is in-ground, roughly kidney shaped with a flat concrete bottom that holds 86,000 Litres (18,917 gallons).
The construction is of hollow concrete block, vertical walls with rebar and Concrete in-fill that has been badly rendered (no waterproofing or fibres).
The thin end of the pond is divided off with a similarly constructed wall to give three narrow weirs to a lower water level section but there is no fall in the ground level to match this drop in water level so it looks a bit weird.
The pond has a waterfall at the fat end which leaks like a sieve as the membrane below it is of polythene which has of course degraded.
The water level is maintained by rain water that drains from the house roofs that enters at the fat end and exits at the thin end.
There is no shelving for plants, no bottom drain, no filter, no skimmer, the pump that did work a very old Oase 40 skimmer is broken (as is the basket in the skimmer).
The only thing that is stopping the pond from becoming a sad stagnant smelly mess is an air pump with four air stones and lots of lilies.
As you would expect, the water is very green and there is about 6" to 10" of crud in the bottom as it has not been cleaned out in at least 10 years!
We have no fish but we do have two ducks.
The pond has now also developed quite a serious leak in the last month which has now stopped exposing the crud in the bottom.

I am a builder, I am practical and I like to do and make things myself if possible.
I currently have the following thoughts…

1. The removal of the dividing wall between the two water levels to make one pond.
2. The addition of a bottom drain.
3. The installation of return Jets.
4. The installation of an in-wall skimmer.
5. The introduction of a slope to the bottom of the pond with sand and then…
6. Install a new waterproof surface, re-render or “rubber”.
7. Due to the above necessary work, I think that the water fall element will have to be ignored for now for financial reasons.

Then there is the issue of filtration and pumping for which I currently have no plan, no knowledge and therefore no clue and which leads me to my questions. Any answers/thoughts/recommendations would be greatly appreciated no matter how small…

1. Should I re-render the pond once the structural alterations are complete or add a “rubber” liner for ease? I think the costs will be similar.
2. If I go for a “rubber” liner, how long should joints between the liner and bottom drains etc last? I am concerned about the longevity of this method!
3. Are my current thoughts on the structure complete nonsense/madness or misguided?
4. Should I add shelving for the lilies as part of the structural works now to free up the pond bottom to allow the bottom drain to do its job?
5. How many bottom drains do I need?
6. Pumping and Filtration
   1. I am very confused about total pump capacity that I need to give pond water turnover, sufficient through the filter and the return jets and potentially a water fall in the future. Any assistance with this would be amazing!
   2. I am thinking about a vortex and a DIY static and moving bed filter on the area near the pond that already happens to be at bottom of pond level. Thoughts.
   3. I have shown a return air line to the bottom drain on my drawing but is there a requirement to introduce more dissolved air considering the proposal to have moving bed filters and the (future) addition of a waterfall? I notice you have a significant sized air stone as well as the moving bed!

My aims...I have to allow the ducks on the pond ~ or its divorce!, I would like clear water and I would like to add some fish.

Help Please!?
Markaw

 

[Mmathis]

Hello and welcome! I’m sorry I can’t help, you are way out of my league. But there are others here with experience. Pictures are always helpful — if you could post some.

 

[addy1]

Welcome to our forum!

What a nice big pond!

I don't do filters.

If it was my pond

1) drain down, clean the muck out
2) fix the leak liner or whatever you desire.
3) (I don't use bottom drains)
4) look into filtering with a nice bog. My first thought was to put a bog where that wall in the pond is. My system is filtered with only a bog, pipes pea gravel and plants. That would make a nice bog.
5) My turn over rate is only about once every 2 hours, with no water issues. But I have a ton of plants filtering the ponds. (11)
6) my water is always clear, no green water, hardly any string algae.

This is a picture at the end of the season i.e when I clean and chop down the plants.
Mine is a wall the water goes back into the pond via the water fall and dribbles over the wall.

This is before I cut the plants down.

 

[addy1]

This is the bottom at around 5 feet down. Under water shot and a shot from above the water. You can see the trap door snails on the bottom and some of the pea gravel that is wandering around.

 

[j.w]

@Markaw

 

[JamieB]

As big as the pond is, and with ducks, you may indeed want to look into using the walled off part as a bog. Meinwhile, as for a liner, consider epdm, which is pretty standard, and you might be able to find at a roofing supply. Unlike some other liners, it is fairly sturdy, and is slower to be damaged by uv.

 

[Markaw]

This is the bottom at around 5 feet down. Under water shot and a shot from above the water. You can see the trap door snails on the bottom and some of the pea gravel that is wandering around.

View attachment 132713View attachment 132714

Thanks for so much advice, I like the idea of a bog filter, could you expand on the construction of yours it's contents (is it just pea gravel or have you included different sized aggregate), maintenance requirements, do you pump in at the bottom and let it rise up to overflow into main pond? Sorry about so many questions! M

 

[Markaw]

I have to say you guys in the US have a much more developed pond industry than we do, and far more kit available to you too. I have just been reading about the snorkel and centipede system and the helix settlement and skimmed systems! So many cool (but expensive) ways of overcoming pond problems that we just don't have here in the UK. We have a DIY, make do and mend war time attitude I think, partly because of a much smaller market and possibly a lack of space.

 

[Markaw]

As big as the pond is, and with ducks, you may indeed want to look into using the walled off part as a bog. Meinwhile, as for a liner, consider epdm, which is pretty standard, and you might be able to find at a roofing supply. Unlike some other liners, it is fairly sturdy, and is slower to be damaged by uv.

I think EDPM is the way for me. If I go for the bog filter idea in the walled off area, it will save quite a bit of work demolishing the wall and save on the construction of an external filter and a lot of digging for the flow and return pipes. That said, I like the idea of the bottom drain as it deals with the duck poop as well as the future fish waste and general rubbish that accumulates in the bottom of a pond.

 

[addy1]

here is a link to how to build bogs , these are the simple ones, no snorkels etc.

Bog building, also called upflow filter, eco filter, wetland filter

I was asked to start a thread on how to build a bog. This is my rendition on bog building 101............. Building a bog: Before you decide to build a bog, you need to know what you want its primary purpose to be. Total pond filtration bog filtration combined with another filter. If you...

www.gardenpondforum.com

Thanks for so much advice, I like the idea of a bog filter, could you expand on the construction of yours it's contents (is it just pea gravel or have you included different sized aggregate), maintenance requirements, do you pump in at the bottom and let it rise up to overflow into main pond? Sorry about so many questions! M

Mine is just pea gravel, around 2.5 feet deep. I have two inch pvc pipes running the length of the bog, under the pea gravel. Slits chopped into them with a sawjaw. I pump into the pvc lines from my external pump (I prefer external) the water then waterfalls back into the pond.

I do zero maintenance, except pulling plants that grow very well, in the fall cut them back (when shutting down the pond) in the spring I rake the bog to remove anything dead, leaves etc. Then turn the pump back on and I can ignore it most of the summer.

My bog has been running since 2010 I have not tried to clean it. One time I opened the drain line, only clean water came out so never did that again.

 

[poconojoe]

My bog is inspired and based on addy's design. Here's my recent bog build thread:

My add-on bog build

I finally did it! I joined the bog club! The bog is approximately 14 feet by 5 feet and about 12 inches deep. I know my 1600+ gallon pond has been overpopulated due to my fish reproductive rates! Last year the water never cleared up to my liking. I figured my two pressure filters and my...

www.gardenpondforum.com

 

[Markaw]

2) If I go for a “rubber” liner, how long should joints between the liner and bottom drains etc last? I am concerned about the longevity of this method!
[/QUOTE]

Any thoughts on the question of longevity of joints in "rubber" liners? I am thinking of the bottom drain connection particularly.
M

 

[addy1]

I would think for a long time, I have not heard of well installed drains failing.
I have a drain pipe in my bog, put there just in case, years ago, nine. It is still holding fine,

 

[GBBUDD]

Welcome aboard . R U N A W A Y F O R G E T YOU FOUND US FILL IT IN AND RUN.

Ok so much for the disclaimer.

I too am a builder and have done a ton of homework before i built my project recently you can see the build below this post in the blue text / hyperlink. Ok as far as the weir is concerned i might make use of one but only as a large particle remover. other wise NAHH . ok that dividing wall across the pond is actually a blessing and you can make that easily into a negative edge or a intake bay. FOR GET ABOUT A MINNISQUEL SKIMMER

I myself like a negative edge and get the leaves dirt etc out of the pond and into one area for a little maintenance. ONE HINT THE WIDER THE TOP the less likely the fish will be to go over the edge. But the way your set up a intake is easier and they work well.
That is also where your pumps will be. and from there I WOULD HAVE ONE FEEDING A BOG and the other feeding your falls down the road. with such a large area i would lean toward the snorkel and aquablox bog as it a lows sediment to drop out of the water before it enters the gravel in the bog. unfortunately you folks across the pond don't seem to like bogs and prefer the weirs and vortex filters OH AND LOTS OF MAINTENANCE. YOU HAVE RETURN JETS TWO THUMBS UP and your thinking of a main drain . now in the summer months and spring and early fall main drains i love they keep heavy sediment from building up but Most areas codes demand two of equal size that if either one was to get blocked by say a child that the suction is shifted to the other drain that can also handle all of the draw from the pump so it can not hold someone under water.both have to be one the same line/pipe check with your local codes laws what ever you folks may call it. the bog i would build off to the side of the pond and have it discharge as far up toward you water fall as i could so the circulation from that an the return jets work together and in time then you can build your big waterfall.

 

[Markaw]

Welcome aboard . R U N A W A Y F O R G E T YOU FOUND US FILL IT IN AND RUN.

Ok so much for the disclaimer.

I too am a builder and have done a ton of homework before i built my project recently you can see the build below this post in the blue text / hyperlink. Ok as far as the weir is concerned i might make use of one but only as a large particle remover. other wise NAHH . ok that dividing wall across the pond is actually a blessing and you can make that easily into a negative edge or a intake bay. FOR GET ABOUT A MINNISQUEL SKIMMER

I myself like a negative edge and get the leaves dirt etc out of the pond and into one area for a little maintenance. ONE HINT THE WIDER THE TOP the less likely the fish will be to go over the edge. But the way your set up a intake is easier and they work well.
That is also where your pumps will be. and from there I WOULD HAVE ONE FEEDING A BOG and the other feeding your falls down the road. with such a large area i would lean toward the snorkel and aquablox bog as it a lows sediment to drop out of the water before it enters the gravel in the bog. unfortunately you folks across the pond don't seem to like bogs and prefer the weirs and vortex filters OH AND LOTS OF MAINTENANCE. YOU HAVE RETURN JETS TWO THUMBS UP and your thinking of a main drain . now in the summer months and spring and early fall main drains i love they keep heavy sediment from building up but Most areas codes demand two of equal size that if either one was to get blocked by say a child that the suction is shifted to the other drain that can also handle all of the draw from the pump so it can not hold someone under water.both have to be one the same line/pipe check with your local codes laws what ever you folks may call it. the bog i would build off to the side of the pond and have it discharge as far up toward you water fall as i could so the circulation from that an the return jets work together and in time then you can build your big waterfall.

Wow, so much info thanks so much, especially the code requirement for the bottom drain. We have no codes (we call them Building Regulations) for pond building which is poor considering the safety issue you raised and as a new grandad this point really hit home!
I was only yesterday reading about the snorkel system! Very interesting!
Any thoughts on the water turnover question the pond is measured in UK gallons so it's about 22,000 US gallons) and therefore pump sizes or the need to add shelving for the water lillies? On the latter point, I am concerned about the many interruptions from the Lilly baskets to the flow and therefore the effectiveness of the bottom drain if I do go that way.I
In you thought process, I assume the bottom drain feeds to one pump that then pushes the cruddy water to the snorkel and the other would draw water into the intake bay.
As a fellow builder, you may be interested in the video of my house I built. At the time of the video there was a lot of landscaping to be done which is now finished bar the pond and immediate surrounding area.

Unfortunately all the preceding work done has significantly depleted any funds available for the pond!
Thanks again for your input and time.
M