I am starting today on the new pond...Tried to design something by my self, but many heads are always better than one...so please let me know if it is OK.
I wanted a bigger pond...but decided not to go 90000 liters but 70000l.
I dont have many things U have there...so it will have to be mostly DIY, simple...functional...easy to clean, cheap...(he he he) and made with what I can find here.
Settled finally on this dimensions:
Inside dimensions 7.6mX 3.6mX 1.8m deep.
Filter 2X7.6X 1.2m attached to the pond...Filter is double...both the same, and serviced by two pumps, each filter has one pump.
The pond will be raised above ground 60cm.
Tried to do some kind of a model...did not draw the second filter, since it will be the same as the first one...
Simple:
BD1 > SC1>Mech filter> Bio...pump chamber...sump
Each chamber has stand pipe, connected to one pipe running under all filters...going to the sump, with another stand pipe at the end..( for peace of mind).I dont have 4" valves here, so I will just put 5 X 2" pipes from the sump leading out, each with a gate valve...Will just have to open all of them when draining it.
Plan to make the sump, the same depth with the filter...will that be OK or I need to make it deeper. I want to put bends on the 2" pipes and expend them to the bottom of the sump so they suck all the dirt..by gravity..will that work?

Will try to put a window, if I find suitable glass here..if not I can add when I get it from abroad...
Want to make the SC slopping with a half pipe buried in the bottom, horizontally, where the dirt will be collecting...continuing with full pipe, to the sump, so I can flush it twice a day...I might order later a automated gate valve...or maybe put airlift on timer at the end...
There will be two 4" pipes connecting the chambers in the filters...more like Erick filter with more horizontal flow..
Turn over rate will be around ones in two hours...not much, but will see what pumps I can find.
two returns at opposite corners...Not sure about the depth...of the returns..In Japan they were on the surface...I dont know U will advise how high above bottom...maybe I put both. Rotation will be around both BD and not around individual BD. I will put aeration on the BD.

Should I put the rotation of the flow around each BD? Which do U think is better.

I will do the BD the Japanese stile, with a second pipe for flushing, grating on top and air above that.

Want to put two overspill in the corners..with basket in them...just about 40 cm deep in the corners...with a pipe under connecting them to the CS. The rest of the corner under that will be filled with concrete and each corner reinforced with Y12 columns...only the top 40 cm will not be reinforced. The water will flow through the basket into the SC...will put a flap to regulate the amount of water going through the weir.
Will put pipes for a third pump to add later and include a bakki maybe later...Now I just need to rush.
Maybe I can put the stand pipes on one side and not in the center, So that I can add K! in some when I get it....for now it will be izeki, izeki and izeki again.
I will put also something to slow the water in the SC and assist settling...Maybe like Mr Tanaka...
I plan to make a bypass for the bio in case of medication...
Any advise will be appreciated...My head is not working properly...need to rush it...and have been sick...for some time.
I want to do the BD like this but much larger...This is a picture from Koianswers...lost the link..sorry.
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something in this lines:
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Please dont spare me, Just make sure I build a good pond.

Colin The question for U is should I put steel reinforced pillows in the center, and corners?
I am using 6" hollow concrete blocks, filled with concrete, walls will be double, with reinforcement in between ad the space filled with concrete.

This is how the BD will be, and it will be flushed eventually automatically, by airlift on timer...
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Sorry lost this link too.
I will put a large pipe in the sump...and make my own airlifts, for flushing.

What is a uni-ring above the BD?

I would skip the "dry chamber" and have ball valves on those lines instead of stand pipes. You dont need a dry chamber.

What type of flow are you hoping for? I see you only have 1 circulation system. The flow through those chambers are going to be slow. I suggest you have a filtration system for each bottom drain. BD->Vortex->1 Mechanical chamber -> 1 Bio Chamber

I wanted to put the dry chamber, since I dont have 4" ball valves here...but U have given me an idea...I can put 5T on the 4" pipe...with reducers to 2" vertically and put the ball valves on the 2" pipes...that I can find...
Thanks...will do that...Then for the second pipe to the BD I can put airlifts in it for flushing...
Uni ring is a porous pipe like from dream Koi that discharges air...like aerated BD.
Will email U the picture ..it is simpler than flicker...

wayneb wrote:

What type of flow are you hoping for? I see you only have 1 circulation system. The flow through those chambers are going to be slow. I suggest you have a filtration system for each bottom drain. BD->Vortex->1 Mechanical chamber -> 1 Bio Chamber

The flow will be in two circles around each BD...There will be two filters exactly the same...so I did not draw the second one...
Skimmers in each corner...
OK I will post it here just now...going to flicker now.

I keep changing the design every evening...
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What type of piping from the BD? Generally one get around 15000 l / h through a 110ml pipe. Each chamber takes away water pressure and speed and you loose about 1500l - 2500l per chamber. I would suggest not having more than max 2 chambers after a vortex unless you are going for a slow turnover and max exposure to media. Think of the Nexus type filter when you design. It is a vortex with, Static Media Chamber and Bio Chamber all in one.

I was thinking ones per two hours turn over...But I might like to increase it...Maybe I include one more BD to make them 3, in case I want to put one more pump???
Then I do the flow like this...going to flicker...
BTW...I did not understand what U mean by the nexus type...
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I will have 3 chambers after the mech filter for bio...My bio is not efficient...so I need more space at list for now...Load shading here...typing in the dark.

Piping is 4" from BD and if it can pass only 15000 then it is too little...But I saw somewhere that it can pass 25000 liters per hour...are U sure?

I am 100% sure. I have pump that does 20 000l/h or 25 000l/h or 30 000l /h and it sucks my vortex chamber dry if the vortex is the only water source. I have a 15 000l / h pump as well and it also sucks the 1st chamber after my vortex dry although this takes a while.

Look here
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Put the roughness coefficient at 150 and the drop at 50cm...see what U get...I get 2800 liters per min...per hour is much more..

Then I have to believe U!
David Soon said that he passes 5000 gallons through his BD by gravity to keep it clean...

The pipe from my bottom drain is 4m long. Look through some of the pond building topics on this forum. Almost all cover the pipe issue.

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The important bits are in Afrikaans.

Jaco wrote:

Ek dog 110mm doen 13000L per uur gravity fed ?

Pieter J de Villiers wrote:

Jaco,

Ek het ook so gedink! Miskien is daai ouens se 110mm pyp groter!

Neville wrote:

Hi Ernst

Nee my inligting is 14000Lt en dit sal nie n verskil maak hoeveel vortexe daar is want na elkeen is dit weer open end so dit vloei begin van voor af.

Maar free flow 14000Lt en ek glo nie daardie pomp gaan jou vortex droog suig nie.

Ernst wrote:

I've had to choke the pump as the water was moving to fast through the settlement vortex - I'm not putting any brushes in!

In short, Ernst has 2 pc-1800 pumps that does 18000l/h each and he is sucking from 2 bottom drains and he has had to choke the pumps back or they suck the chambers dry. Pieter and Jaco was right.

Thanks...it helps a lot what U told me...Do U think two pumps by 0.75 spek...will manage the pond?
I can add one more later for a bakki if it is not OK...The pond will be a bit less than 70000liters.
My laptop died...thanks God the electricity came back.

A Porpoise 0.75kw will do 24 000l/h. How many suctions lines do you have? Only the Bottom Drains? If you are only sucking from the bottom drains then you are going to have a problem to give enough water to 2 0.75 pumps. The more suction areas you have the better.

If you haven't bought the pumps yet you must have a look at the Speck Eco-Touch. I have 2 they are amazing.

I can put the pump to suck from a skimmer with prefilter...regulate the flows with valves...so it does not dry the filter...
Now u have scared me...He he he!
More problems to resolve...considering the restriction of the media...the pump for sure will dry the last chamber...
What should i do?
How many pumps...how to solve this problem???

I did not buy the pumps yet...Have one but not sure if it is purpoise..???
I dont have much pumps here...Maybe I will use a swimming pool pump...electricity is fixed charge here.
The only one I can find here is quality...SA pump.

1 Bottom Drain suction line and 1 skimmer suction line should provide each pump with enough water...but now you are going to need Ball Valves again.

To get around the flow issue between chambers you can add 2 or 3 110mm pipes between the chambers but your bottleneck will be the incoming 110mm pipe.

Quote :

The only one I can find here is quality...SA pump

0.75kw pump and it only delivers 16 000l/h but at a higher head than the porpoise.

I was planing to put two 4" pipes between each chamber...but I can only use 2" pipes or 4" pipes...no other pipes here...or fittings. So in and out of the pump I put a Y and run double or triple pipes...in and out of the pump...That is what I did on the old pond.
Now I was planing to use overflow, by gravity to SC...now I have to change the skimmer set up to accommodate some kind of pre filter...not to clog the pump.

Lets say...I use two quality pumps...will they be enough for the pond? It will be a bit less than ones in two hours...maybe ones in 2.5 hours...
On this pond i pump with a spec from the pond through a SF in a gravity fed 3 chambers very large...At the end of the filter...the 4" pipe that feeds my returns...is only half full with water...
The second pump is quality...and goes through a different filter.
Need to make new plans again...what a headache..
but U saved my life!