Hi Cliff,

Yes I think that will be ok.

Wet those sides a bit tonight. The concrete must not go onto dry ground.

I am in serious pain today.....people are coming to lay the ready mix at 10am this morning and I have a meeting at 10am that I could not get out of.......luckily it takes a while for the ready mix to be dropped off and I live 5 mins down the road.

Oh hell.....how am I going to get thru this meeting!!!!!

Hi Cliff

Just take a nap man

Jurra but these okes are fast

10h51

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10h53

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11h28

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11h41

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12h02

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Yurra I agree,

That is like a dash of speed, well done glad to see that they keep it agitated while packing.
Good stuff Cliff, it really looks like something to me. I think the fact that it is continues cast, makes it a better shell than bricks, bricks is only as good as the mortar and placing between bricks.

And then of course the cost and time factor.

Hi Neville,

I'm a very nervous\paranoid person. Thats why I went the concrete shell route, heard it is by far the strongest, safest option. The worry about having enough concrete now is over as I had a bit too much, better too much than too little. Now my next worry is the joining of the 2 walls.....will be sealing it on sealing day which hopefully will be monday (plastering on friday).

Will be sealing the join with a product from cemcrete called permastop. Then hopefully water by wednesday next week

Some more pics

12h52

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13h28

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Hi Cliff,

When you plaster remember the plaster key (or similar) especially at the joint area.
Careful on the filling, I would only fill from 7 days after plastering, 30% per week, but keep the walls wet as often as possible.

And now remember the new pond sindrome issue, talk to pieter about that, he knows it well.

Hi Cliff

looks good! How much concrete did you use 4.5 cubes?

Yes, 4.5cubes which ended up being too much

Hi Cliff, thanks for sharing and keep us posted.

Hi Cliff
My twopence worth : I think you're rushing the process in the final stages. Concrete needs to cure sufficiently, and I was advised to wait between 3 -4 weeks before adding water. You don't want to place unnecessary pressure on the concrete structure. A future structural failure so close to your home could be disastrous. But, perhaps with the "poolmix" concrete the processes and time frames are different.
Thusfar it's really looking good.
Regards
Jack

Hi Jack (no pun intended...lol)

I spoke to a couple of pond builders about this and what I was told is that it is actually better to plaster and seal sooner (3 days after concrete shell to plaster then 3 days after plaster to seal, then 3 days after seal to fill) because with the cold water in the pond it slows down the curing process of the shell thus creating a stronger shell and a shell that will be less likely to crack. However I will most probably be plastering on friday, I will then seal next week tuesday and then by the following saturday start to fill the pond.......i'm told that this is sifficient, will confirm this again with 2 or 3 other builders before I proceed with filling. However, I do know that it is fine to plaster on friday and to seal on tuesday.

Maybe Colin Hunt can comment???

Anyways, here's some pics now of the shell complete

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Hi Cliff
My concern would have emanated from your initial posting which said that you wanted to add water next Wednesday. Contact the Concrete and Cement Institute. Website [You must be registered and logged in to see this link.] There I read that concrete reaches 80% strength at 28 days, but 40% after 1 week. Will 40% will be structurally enough to carry the structural pressures and tensions exerted by a largish mass of water? Alternatively, speak to a structural / civil engineer at the company that provided your poolmix. I'm sure they'll give you sound advice.
I want to do my next pond this winter, hence my comments / queries. My current pond was not packed, but built with concrete base / foundations, and brick walls, but your option is certainly worth considering. Hoping to learn from what others do. So please let me know what advice you receive.
Regards
Jack

Cliff are you going to fibreglass? I ask cause i see you joined your old pond to the new. I did that and thought i would get it right.

I dug out underneath the old pond floor about 30cm in length and 15cm in depth and my new ponds floor went under and over the old ponds floor and walls.

In the end i had to fibreglass as i had leaks. Hope you have more luck.


One last thing, is the new pond level with the old one?

Hi Jack,

I do hear your concerns, especially with the volume of water being that much greater, let me find out from the pro's and see from there. Rather be safe than sorry.

Let me give the guys you mentioned a call and follow from there, with my current pond I did the shell, then plastered a week later and sealed 3 days after that then filled with water 3 days later and up till now never had a problem........tho that was just 8000lt's and now we're talking +30000lt's

Maybe I should delay the plastering till next tuesday and then seal next saturday and then fill on tuesday the 15th...that will then give the sheel 14 days at least. Maybe that would be better.

Rather safe than sorry....thanks Jack

Hi Wayne,

I wont be fibreglassing. I did have a look at your pond setup recently, never knew till a few days ago you modified your pond.

Think the 2 ponds may differ in depth slightly, the 2 shells are completely seperate, only joined at the wall. If I do have a leak then I only have to drop the level of the pond by 500mm to do repair work. I will be using permastop from cemcrete to seal the joins which I have been told is an awesome product. I actually sealed my current pond's bottom drain with it and never had a leaking problem.

I know that joining ponds is a no no, but with specific pond builders that I have spoken to they have advised that they have done many pond joins and renovations with great success and no leaks, they have offered advice which I have followed and hopefully I do get it right, if not then at least I will not have a pond that runs dry.

My penny's worth Cliff
Most companies will not guarantee a paint on a sealing product unless the plastering has dried out for at least 21 -28 days, depending on weather. The alternative would be to have a test done on the plaster to confirm the moist content before sealing.

Hi Cliff

Jack and Bobby is confirming my concers to you.

Don,t delay the plastering that can and should go on as soon as possible, so as to form a better bond with the shell.

I hear what you say about your previous success but still just confirm again with your suppliers.
Definitely don't fill that pond at once I would really think 30% per week will be fine after you have given the plaster a week to stand but water spray twice a day, Concrete should be kept wet till matured.

I will continue with the plaster on either friday\saturday. I will then leave the plaster for 7 days and then seal the pond. After sealing I will wait another 3 - 4 days and then look into filling the pond.

That would give me a total of around 2 and a half weeks before adding water.

Would it be a problem if I sealed with the waterblok and only added water 7 days after, I'm just worried that the waterblok dries out too much. Was told that the waterblok must be left for 3 days after coat and then filled with water.

Just dont want the plaster to dry out too much before sealing, so 7 days here would be my max, 7 days after plastering I want to seal with waterblok, just want to know a longest period for leaving the waterblok on without filling up.

Hi Chris

My office is close to the waterblock people, I will go there tomorrow and check up, Things don,t ring true to me here. I will let you know.

Hi Cliff
Did you get specialist advice, or have you just extended your programme? Please advise so that I - and others - can learn. I believe that it must be a koi keeper's nightmare if one's pond fails structurally and leaks dominate what is supposed to be a satisfying hobby.
Regards
Jack

Hi Jack

What do you mean I have been giving him advice all along

Neville...dit is vir my 'n groot bekommernis! Op die forum erens... is daar nie 'n 'posting' oor jou veggiedam wat lek nie?

Ek oorweeg ook 'n pondliner. As ek 'n dam soos JasonR met geleidelike 'slopes' gebou het dan het ek in daardie rigting beweeg, Maar miskien sal ek 'n nuwe thread begin.

I spoke to a couple of pond builders about this and what I was told is that it is actually better to plaster and seal sooner (3 days after concrete shell to plaster then 3 days after plaster to seal, then 3 days after seal to fill) because with the cold water in the pond it slows down the curing process of the shell thus creating a stronger shell and a shell that will be less likely to crack. However I will most probably be plastering on friday, I will then seal next week tuesday and then by the following saturday start to fill the pond.......i'm told that this is sifficient, will confirm this again with 2 or 3 other builders before I proceed with filling. However, I do know that it is fine to plaster on friday and to seal on tuesday.

Maybe Colin Hunt can comment???

Hi Cliff, Sorry I only spotted this now. The idea is to slow the curring process of the concrete, so I would say that five to seven days after packing you can fill it with no problems at all with the steel and the soil is also there to give support. If you have ever tried to break 25 mpa concrete after four days you will understand what i am saying. As for the section joining the old pond with the new. As I explained to you I would drill 11mm holes in the old section 250 - 300mm appart and dowl it with 10mm steel reinforcing to tie into the new concrete shell. Before packing that section, wet thoroughly, and pour sluge over the old concrete to create a stong bond. This should do the trick but it is always a possibility that it could crack therefore a very good sealer, preferbly glass fibre even if it is only 400mm either side of the joint. Good luck, you won't have a problem.

Plastering happened yesterday....finally......plaster is very thick, must be 40 -50mm thick.

Will finish the tiling around the top on saturday, then permastop all the cracks and joins nice and firmly and then seal with waterblok.

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