I have started with foundation on a new above ground selling pond this morning and I am going to try something new. Dimensions: 20 meters x 1,2 meters x 1.2 m depth = 28 800 liters (including 4 filter chambers)

Step 1, Build a thin outer wall with 90 mm blocks with support colums towards the outside every few meters. No slab at this stage.
Step 2, Place a 500 micron liner inside with 2 x 110 mm liner bottom drains. Liner to cover the floor and walls right to the top, to make it 100% waterproof.
Step 3, Throw a slab on the floor on top of the liner (iron reinforced)
Step 4, Build another (inner) 90 mm wall on the slab next to the outer wall to cover the liner against the outer wall, leaving space between them for concrete.
Step 5, Put iron reinforcing in the gap between the inner and outer wall next to the liner and fill with concrete.

Expected result: Strong wall of 250 mm (90 + 90 + 70 gap filled with concrete) , No sealer needed due to liner and I believe I should never have problems with leaks and the liner will last for ever as it is imbedded in concrete, and you will not see the liner.

Any advice, comments will be appreciated.

ja paul al wat ek kan se happy hunting met die bank manager dit gaan `n paar moelas kos glo ek

Hi Vossie, al wat regtig bykom is die liner. Ek kry 500 micron liners @ R 20 per vierkante meter.

Dus, vir die pond R 1440 ekstra vir die liner. Ek spaar egter weer die seeler wat soveel sou kos, en hoef nooit weer te seel nie.

goed om so te dink as mens `n nuwe pond bou en van scratch af

Hallo Paul
Ek dink die konstruksie gaan moeilik wees. Dit kan nie maklik wees om op - en binne - die liner te bou nie, sonder om die liner te beskadig. Enige lekkasies later sal jy tog moet seel. Dit klink goed maar ek glo nie dis 'n praktiese oplossing nie. Wat van pH laag te hou -en stabiliseer met sement laag in direkte kontak met water?
Groete
Jack

Hi Paul

I,2 meter is nie hoog nie, my up en under filter loop al paar jaar en dit het net n enkel muur,

Bou jou dam met n enkel muur en fibreglass hom jy sal ook nooit weer n problem he nie.

Vra vir Colin om vir jou te verduidelik hoe lyk Costa se verkoop damme se design, dit werk baie lekker.

Hi Neville
What volume would a single wall fibre glassed be able to hold without leaks ?

Nasief

Fibre glass done properly just don't leak at all.

Fiberglas on its own is very strong, you just need the wall to help it keep it's shape. If the depth are not too great it will hold any amount of water as the weight is not all centered to a point. I don't have the formula to support my theory but a 100 meter diameter pond will have the same or very little more pressure against the wall as say a 10 meter dia pond will have. The pressure or weight, increases as we increase the depth, by more than it will increase, if we increase the diameter.

Thanks Neville

Something to consider for the new pond

Jack Bach wrote:

Hallo Paul
Ek dink die konstruksie gaan moeilik wees. Dit kan nie maklik wees om op - en binne - die liner te bou nie, sonder om die liner te beskadig. Enige lekkasies later sal jy tog moet seel. Dit klink goed maar ek glo nie dis 'n praktiese oplossing nie. Wat van pH laag te hou -en stabiliseer met sement laag in direkte kontak met water?
Groete
Jack

Hi Jack, I realise that the builders will have to work very careful not to damages the liner. This is why I decided to go the 500 micron route. I have to admit that it is still a concern.

I am not too worried about the pH. The concrete filling between the two walls will be between the outer wall and liner, and the water will only be exposed to the inner wall and floor and I will seal it a bit with an inexpensive sealer.

Neville, I have always believed that fibre glass is the best option. Pitty it is so damn expensive and I hate working with it.

I see this more as an experiment. If it don't work, I will redo with Hydro Seal or maybe fibre glass.

Neville wrote:

I don't have the formula to support my theory but a 100 meter diameter pond will have the same or very little more pressure against the wall as say a 10 meter dia pond will have. The pressure or weight, increases as we increase the depth, by more than it will increase, if we increase the diameter.

This principle can be seen when calculating the thickness of an aquarium.

The required thickness is based on the amount of water pressure:

[You must be registered and logged in to see this image.]

The depth is the most important factor and then the lenght of the tank. The width of the tank is irrelevant.

The same principle applies to ponds or viewing windows on ponds. The width of the pond will not influence the required thickness of the wall/thickness of viewing window.

Dankie Paul

Admin wrote:

Step 1, Build a thin outer wall with 90 mm blocks with support colums towards the outside every few meters. No slab at this stage.
Step 2, Place a 500 micron liner inside with 2 x 110 mm liner bottom drains. Liner to cover the floor and walls right to the top, to make it 100% waterproof.
Step 3, Throw a slab on the floor on top of the liner (iron reinforced)
Step 4, Build another (inner) 90 mm wall on the slab next to the outer wall to cover the liner against the outer wall, leaving space between them for concrete.
Step 5, Put iron reinforcing in the gap between the inner and outer wall next to the liner and fill with concrete.

Expected result: Strong wall of 250 mm (90 + 90 + 70 gap filled with concrete) , No sealer needed due to liner and I believe I should never have problems with leaks and the liner will last for ever as it is imbedded in concrete, and you will not see the liner.

Any advice, comments will be appreciated.

Despite the advice against it, I did proceed with the concept of liner/concrete and hope it is going to turn out fine. At least the experience will hopefully be worth the effort.

I was extremely busy with other projects and could not even attend to the forum and therefore had a few postponements but will finally be able to fill next week.

The gap between the two walls (to be filled with concrete on the outside of the liner) is not as wide as instructed, but no turning back and should be strong enough.

Herewith a few photos:

[You must be registered and logged in to see this image.]

Lyk baie goed Paul, ek sal jou seker sien oor die volgende paar dae, hoop ons kry n kansie.

looking good Paul!

Paul,

Are you getting any Tosai from Japan this year???

Thanks.

Hi Tony

I am finalising my order at the moment.

Kind regards

Hi Paul,

Ok, i c....

Once you finalised the orders...

Please give me more information about the breeder and size of the koi, if you don't mind.....

Thanks.