Airlift powered pond build by Smetjen

[Pssymon]

The second pond build to be shared on the site, is by user Smetjen (Geert).
This is a very clean build as well. After sharing some ideas on the forum the floor-plan was adjusted and the build could be finalized.




Airlift powered pond build, by Smetjen

The updated plans that were created with help from the forum members:






This is the floor plan drawn to scale. In the top left there will be an Airlift which only purpose is to create a good current in the pond and if possible, move floating debris into the skimmer. Three bottom drains will be installed, one of these will be aerated. The shallow area is created because this area is very close to the neighbours' house which could be risky when digging.

The filter floor plan:



The three bottom drains all connect to the first chamber which will also house the skimmer. A valterra 90mm valve is installed at the bottom of the skimmer so it can be closed and the chamber and drains can be cleaned.
In the extra chamber there will be another transit which will allow the placement of a trickle filter in the future, which will connect to the moving bed filter. The pond will run with one Airlift with a secoh SLL-40 pump which should give enough flow. A second transit will be built in just in case one Airlift is not enough.




This is the section view of the chamber with the Airlift and the control room. The chambers all connect to each other with three 125mm transits to be absolutely sure there is not too much drag. The Collector will be built in two parts, as this would otherwise be in the way during the build as it will be enclosed in the concrete floor. The concrete floor will be poured in one go as this is the cheapest way to do it. Afterwards it will be covered with a cement floor. Every chamber will have a 90mm drain pipe and will connect to a chamber with a pump to get rid of the dirty water.





Section view of the chamber with the japanese matting and the moving bed. The matting will not be aerated (for now) as this water directly flows from the moving bed where it has been aerated already.
The (future) trickle filters' drain will also connect to the moving bed chamber, this will have a VDL valve as the trickle won't run in winter and this could cause trouble when it's freezing.




The section view of the first chamber and the static bed chamber. Here two 200 micron Crielsieves will be placed which each will have a 160mm transit into the static bed.
This chamber will also house the skimmer with the Valterra 90mm valve, as mentioned before. Below the feeding valve another valve will be placed with a detachable coupling.



A picture of one of the first purchases for the project:



This will serve as a temporary home for the fish.
This big pool will also allow for a large amount of the current pond water and bacteria to be used again to start up the new pond.



After some tips on the forum, the plans were adjusted again.
The second outlet will now become an inlet for the filter. An Airlift in the last chamber, running on a 30w air pump, will run this. Together this should give about 26000 litres of flow through the filter.
The skimmer will get its own Airlift as well, running on a 20w pump. This should improve flow through the three drains as the 40w pump now only has to run these without the added skimmer.



The demolition of the old pond has started, these are some pictures of the way it looks now:




The reeds have to be removed as the drainage system will be placed and these are in the way.




The pond will just become 10cm wider, as much more than that would cause it to no longer match the sliding door.
It will be built 130cm into the terrace however, so it will be closer to the house. At the other side it will become 20cm longer.
The entire pond will also be raised to 30cm above ground level to prevent leaves blowing into the pond.
The fish will have to stay in their temporary home for about two months while the build is finished.




Later, the drainage system is installed.
It's advised to place the system 10-14 days before digging starts to be sure that groundwater will not be an issue.

Some pictures from that morning, first the holes had to be handmade with a soil auger to get to the required depth. (Geert in the picture below)



After that, the filters can be connected to the main suction line going to the pump.




Now the pump can start running. It will take over 10 days before the digging will start from this point.
Before that the pond and a part of the terrace will be removed.


The PVC pipes and bends have been delivered. It's amazing to see how much goes into the pond.




This is almost everything, just the two Collectors and two Airlifts that have already been made are not in the pictures.
The next day work is continuing on preparing the garden. The fish are staying in the pond as long as possible due to freezing temperatures at night.




Continuing work on removing part of the terrace.



All 1470 bricks have been brushed clean by hand as these are going to be used to create a new path next to the finished pond.



This afternoon the building blocks were delivered a day early, which meant they had to be moved by Geert alone.




After asking where the blocks had to go, and being told that everything had to go through the garage into the garden, the driver wished him good luck with it.



All blocks had to be moved by wheelbarrow through the garage into the garden.








Continued in part two!

[Pssymon]

Part two:


After moving a lot of the blocks with his dad, it's time for a break.



The neighbours and Geert's wife coming to help:





This is what's left after moving blocks for 4 hours. The rest is done the next day.




A picture of how the garden looks at this point:




Now the time has come to completely remove the old pond before the new hole is dug.
First the temporary pool is filled.



Moved the Koi from the pond into the pool:



4 of the Koi are moving out, the rest is staying.


The pond has been pumped out and cleaned. The Oase pump is visible in the photo, which has been running for 10 years. This big energy consumer is no longer needed as it will be replaced with an Airlift!




Removing the liner and underlay.




Then the old concrete had to be removed, which turned out to be a serious job.

Another photo of how the hole looks at this stage. Everything between the orange stakes has to be dug down to 165cm.



Before the digging started, Geert dug a hole 10cm deeper than the required depth, to test the drainage system's effectiveness.
Luckily there was no ground water seeping up at all, so everything was looking good for the dig.



The next day at 8AM, digging started:




The ditch had to be filled so the digger could cross:





After digging for about an hour, the first problem arises. There are a couple of cables in the way...




After a lot of phonecalls and chatter, a technician showed up to check the cables.




One of the cables needed to be checked by a different technician, causing even more delays.
But then luckily, the cables can be removed as they are no longer in use!





Here Geert checks the depth of the hole. He used a waterlevel to set a couple of reference points and attached a cord so he could check the depth.
You can also see the first part of the structure which will become the temporary roof over the pond.







Finally at the point where the pond is almost entirely dug out. The final bits in the corners have to be dug by hand as the view from the digger is limited here.





The construction of the roof continues. Nylon cords are tensioned over the frame to prevent sagging of the plastic roof.
Not ideal, but hopefully this is enough to protect the build from the bad weather.




Now everything is dry and protected, and the bottom drain locations can be marked.




The first bit of piping can be placed. A lot of careful thought and measuring has to be done to prevent any problems that can arise later.




After making sure everything is placed correctly and the bottom drain is level, it's partly dug in to make sure it does not move at this point.



Later the drain and pipe were completely covered and the sand around the pipe was compacted.




Continuing with the piping, gluing, measuring, cutting...




Unexpected help arrives (Geert's dad). This is very welcome as the work has to be finished before the concrete is being delivered.




Placing the skimmer drain. This will all be pressure PVC as a precaution.



Geert built a template to neatly house the 3 bottom drain- and skimmer pipes. This way they cannot move when the concrete is poured and you end up with a nice precise placement.




Here you can see the chimney pot which is placed a bit deeper and sits on 4 spacers. This is done so it will nicely seal when the concrete is poured. The reason this is placed here is because this will become the lowest point of the filter pit. A submersible pump will be placed here, which will effectively pump out all of the waste water.





This morning the Collector's were placed. The one in the back is only 1 meter high, this will be figured out later since it's going to be placed inside the pump chamber.



At this point everything that will be under- and inside the floor has been placed.
Everything is made as level as possible with a rake. Then some plastic foil is placed to contain the concrete and prevent the moisture from seeping into the ground during the curing process.
Two layers of reinforcement are placed as the pond is situated above an old waterway.




Here, everything is ready for the concrete to be poured. Placing the reinforcement was finished just 30 minutes before the concrete truck arrived.



Geert's dad worrying about the whole thing.



The pump truck has arrived:



Shortly after that the concrete truck also arrived with the required 7,5m³ of concrete.





This was taken after the concrete was all poured. An important milestone in the build.

[Pssymon]

Part 3



After the floor has been poured, a friend of Geert came to help establish the height that the pond should become, by using his laser leveler.




Since it was still early in the day after that, the bricklaying was started.



The first out of 1270 blocks.




A couple of blocks on:



The result in the evening after a couple of hours of bricklaying:




This is after another day of bricklaying. In the picture you can see half hollow blocks that have been placed sideways. This is done so the rebar can be extended into these hollow blocks before pouring the raised plateau which will be situated here. This should provide some extra strength.


A picture from the other side of the pond:


Cutting one more block:




Since the wind was an issue, the roof had to be dismantled.
Between the downpours work was continued. The first layer of the filterpit was finished together with the required drain pipes.


The materials for the shallow area were delivered as well.






The plastic and rebar is placed so the floor can be made. The pictures show how the rebar is put inside the hollow block to connect and strengthen everything.




A 315mm PVC tube is used to get the concrete where it needs to be, without damaging the pond edges and surroundings.


The result after one night of drying:




There are some worries about the huge mess.



A few days later things are starting to look better as more rows of blocks are added to the walls.





The weather forecast predicted more rain to come, so the roof had to be redone again so the bricklaying could continue at a fast pace.
This time the plastic roof was tightened to the frame some more to prevent wind damage.



After another day's work Geert was back on schedule:





The result after another day working in the 'pit' as it was called:





Some pictures of how the blocks were moved on to the floor:





Since the tube that supplies the Collector will run alongside this wall over a 10 meter length, some supporting blocks are placed to make sure the tube cannot break or sag.




Test fitting the bends. This will make glueing everything together easier:




Now everything can be glued together. The Collector transit sticks out 3-4cm into the Collector (more than enough). The transit has been sealed on the inside with some glue as well.




This photo shows how the tube will be placed. The area behind the wall has been filled with sand up to the level of the supports (about 1,2m between them).



This was done before the wall was made to full height, as that would make the tubes difficult to reach and glue.



Another row has now been placed and the shallow area is looking better.




The filter is now reaching a height where it's difficult to step over the walls, so some old boards are used to get around.




Now the walls are at the height where the dry area in the filter needs some openings fitted for electricity, tapwater, the submersible pump, etc.






The current wall height:




The shallow area which now needs two more rows of blocks.




The start of the last row:




This is the point where the first skimmer has to be built into the wall, shown on the picture here. As you can see this has been modified to fit a 110mm pipe since this will be running on an Airlift!




The downside of all the progress is that it's getting more and more difficult to get around without hitting your head on the temporary roof. Measuring is becoming more of a challenge as well.




In the foreground of the picture above you can see two large pipes that are partly built into the wall already. These will become the transits behind the Crielsieve which will lead to the static bed. These pipes are 160mm in diameter to be absolutely sure they won't be a bottleneck.


The board which was used as a block slide will have to go now as the wall has to be finished.




Nearly there!





Here the skimmer and the trickle return have been fitted. The trickle filter is a plan for later, just the preparations are made in advance so it can be easily installed later without having to go through the wall again. Behind the wall a VDL knife valve will be used with a watertight cap at the end to make sure this will never leak.




At this point one side of the pond + the filter compartments need one more row of blocks before the second skimmer can be placed.




The skimmer is now placed, and if all measuring was done right this should all line up perfectly.




This marks the end of all the bricklaying activities which is a big relief.
The pond is now cleaned up, since there is some time in the day left a start is made with the plastering:





After starting the plastering, Geert decided to try and finish plastering the entire pond the next day. This worked well untill work on the second wall started, and the plaster started to nearly fall off the wall...






After a day of looking for the solution, Geert asked the forum and received some tips.
Then the plastering continued. Starting with the filter compartments this time. This wasn't as easy as expected, especially when you're a tall guy.
The transits in these small spaces don't help much either.
After one and a half days work on the filter is done. The polyestering will be done by a specialist later.





Two chambers showing the transits that are in the way a lot:






For a change some more bricklaying has to be done.





Here a large part of the pond has been plastered, which is a much easier job than the filter compartments!



Some beer to keep spirits up..






After plastering was finished, it was time to apply the surface finish (screed) layer in the pond and filter chambers.




The first load of screed is ready to be applied. In total about 4,5m³ has to be moved to the pond with the wheelbarrow.




To be able to reach the bottom of the filter compartments, some creativity was needed to properly reach everything.



A couple of hours later the surface finish is competely done. Another step closer to the end.



The look of the pond really changed after this layer. The shallow area looks much better now. This area slopes down 23cm on a length of 135cm. This should be steep enough to prevent debris settling.




A view of the first filter chamber where the bottom drain and skimmer connect to. In the middle you can see the drain.




Another picture of the finished layer in the pond:



This layer now needs to dry for 14 days before the polyester layer can be applied.

[bryanangler]

Dude your progress is fantastic. Thank you so much for sharing this!

[Pssymon]

Thank you for your comment Bryan, I will let Geert know when the topic is complete. If you have any further comments or questions feel free to add them here.

[Pssymon]

Part 4


Another update.

The plastering at this point had been changing colour as it should as the weather had been good all weekend.
Things were looking good and the weekend that had been planned to do the polyestering looked to be reachable (the underlayers need to dry first).

A couple of days later it sadly started to rain. 26 litres of rain came down in just 7 hours.
The soil around the makeshift roof was not able to cope with this much water all at once. All of this water sought the easiest way down, which was straight down the outside of the walls of the pond.
Since the conrete floor is a bit wider than the walls, the water pushed its way between the rendered floor and the concrete base, coming up into the pond through the bottom drain holes.
Even the drainage system was not able to cope with this much water at once.




Everything had dried nicely, but now the photos above show how everything has become wet again. This will take multiple days to dry once more.
If the pond does not dry before the planned date, the polyestering work will sadly be delayed by two weeks.


While waiting for the render to dry there is more work to do.
The next job was to render the outside of the pond. To shield a bit more against high temperature fluctuations in the pond, the outside walls are rendered about 30cm below ground level as well.

As there was not enough power cable available from the old pond, some new cables had to be laid to provide the new pond with enough options to connect everything up.
The pond will be filled (and topped up when needed) with tap water as the groundwater is not a good source in this area. This had to be connected as well which took a good number of hours.



This is the last connection, which can be closed off and removed when needed.


This faucet was placed to make it possible to completely shut off the water, in case of freezing temperatures (to prevent damage to the pipes).
The power cables had to be laid from the control cabinet up to the area where the water pipes lead out of the house as well.

Geert attached a good number of outlets on PP (polypropylene) plate. A friend of his helped him to connect the outlets to eachother.
Doing it on your own turned out to be a bit of a challenge without the needed experience.


The endresult. The result looks good but time will tell if all wires are connected correctly!


This photo shows that two individual boards are used. This is intentional as each will have its own relay. Each outlet has a switch to prevent having to pull the plugs out all the time.


Next the water supply and power lines had to be dug in the ground at around 40cm deep. This meant the terrace had to be opened up:


In this corner the water pipe will be connected, the power cable will also come through here. A cover will be made later to prevent frost damage.


While digging next to the terrace, some piping was in the way (as always)


Before placing the polyethylene tubing, both ends are taped off to prevent soil falling in there as the tube is pulled through the trench.


To be safe, another extra tube was placed with a good amount of drawstring for possible future connections (maybe pond heating). This way the terrace does not need to be broken up another time.



After working for a couple more hours, everything was placed and connected and the ditch could be closed again. Before closing, the water pipe was pressurised to see if everything sealed tightly.
Now the terrace can be restored again.



By now the mini Collector was made for the pond overflow, this will also house the level indicator. This was built by using the one made by Koi.Gin as an example.

First a small 28mm hole is drilled, we want to end up with a 50mm transit in the end. The hole is first sanded smooth to prevent tearing when stretching the material.
An earlier attempt failed because this step was skipped, so it's not advisable.


Now the tool that forms the collar has to be made.


When this is finished we can start making the collar.


When the edges of the hole are weak enough, the tool can be pushed through. While doing this the tool is being turned and cooled with water to prevent too much shrinking of the material.



The Result:



After some more work:



This sliding PVC sleeve is used as the pond overflow and also directs excess water to the sewer.


After more measuring, sawing and gluing, this is how it looks. The top pipe is the pond overflow, the bottom one serves as a drain, should this ever be needed.
On the right you can see the inlet from the pond which can be closed with the slidevalve.


This has not been mounted yet, as this chamber will be completely fibreglassed as well to keep a uniform look and improve the ease of maintenance.


Meanwhile, the overflowpipes which will be used in the moving bed chamber have been finished. These only need to be shortened to the right length later.
To make sure these pipes would allow for enough flow, Geert calculated the total surface area of the openings, which comes to 128cm². A normal 125mm pipe has a 120cm² opening so this should allow at least as much flow.


Three of these pipes are needed, which requires quite a lot of PVC.


The openings are 10cm high, as the sliding sleeve can just fit over this length, making it possible to close the pipes.


Here the sleeve is in place, making it possible to close off the two adjacent chambers without losing 14 to 16cm of water. This would mean a loss of 300 litres of water every time. The water will be changed enough when flushing the drains anyway.




While the pond render is still drying, some other things can be prepared.
At this point a Crielsieve was built by Geert.

This was made out of PPH plastic which can be welded together using an extruder.
First the sides were cut to size and slots were made where the sieve and sealing plate can be placed later. The hole seen at the bottom is meant to house the small aircollector later.


Before welding everything together, you have to check if the sieve fits properly. It wouldn't be the first time that such a mistake was made.


On the outside of the triangular piece the connection for the airhose can be seen.
After checking the fitment of all the pieces, the welding can begin. Some caution needs to be taken as the plastic can warp due to excess heat.



Another connection is welded to the top of the sieve frame.


The result after a while:



The next step is to mirror all the previous steps for the other side. This wasn't as easy as Geert had hoped.

This is the top view, you can see the valve that regulates airflow to each sieve individually. With this setup you don't need to get your hands wet.


The view from the front, this is how it should look in the pond.



The holes drilled in the collector are 0,5mm in diameter. One hole is drilled every centimeter ( a tip from a Koivrienden user). Should additional (or larger) holes be needed then those can always be drilled later.

Now the pond has to be finished further before the Crielsieve can be placed. One step closer to the end..



Epoxy render has now been applied to the corners of the pond. This is done because this type of render is easier to work with, and easier to finish compared to normal render.
This render is made by mixing four different components.

A friend of Geert advised him to tape a piece of plastic foil onto the render after a couple of days. Even if the render looks dry this can sometimes be deceiving. 6 days after the render was complete the walls looked dry, at this point Geert taped the foil to the render.


After leaving the foil for 13 days, it was finally removed. Geert was very surprised to find that his feeling was wrong as there was still moisture in the render.


Still too early to apply fibreglass, knowing that moisture is the enemy when doing this..


Rounding the corners with the special render, a half piece of pipe was used to easily create these rounded corners:


Geert had to keep a distance of 5cm from the skimmers in the wall while applying the normal render. The reason for this is that his friend used the same epoxy render in these areas which adheres much better to the plastic skimmers. After curing this becomes rock-hard


After the corners were done, Geert had another job for his friend:


After a while he stopped smiling..




Al in all this wasn't a very enjoyable job, as every bit of render needed to be completely smooth. Otherwise Geert would have to take off any sharp edges with a grinder afterwards.

This is what a finished corner looks like. It has been flattened out towards the top to make the fibreglassing easier.




The next update will show the fibreglassing progress!