Cement Fish Pond

[bubbaba]

I need a little help. I am building a cement fish pond apprximately 20 meters by 12 meters. The pond will be in some places 1.5 meter deep and in other parts 2 plus meters. Around about one-third of the ponds edge I will have a shelf about 50 cm deep runing 3 to 4 meters from the edge of the deep parts. I am building on soil that will not hold water.

For a cement collar/beam around the circumfrence of the pond, what specs should I use. How wide? How thick? Size and amount of rebar, iron, or welded wire, etc? I know and want the beam, but, I have no idea abut how much reinforcement I should use or the size of the beam. In addition to the support the collar/beam provides to the edge around the pond, I want to be able to work claydirt around to the edge so that grass will grown right up to the wates edge and no cement showing.

The pond will be used by the family for food and recreation. Mostly catfish and talapia. No commercial.

I would appreciate all the help/advise you can provide. Thank you.

[jaiyenyen]

Hi bubbaba,

I have a very similar project on the go at the moment. The hole has been dug, I am getting prices of between 200,000 bht and 600,000 bht for the concrete. I have also thought of a UPVC liner, but no prices as of yet, and to be honest, I think I would worry about it getting a hole and leaking.

I shall watch your thread with interest.

Regards Jaiyenyen

[Issangeorge]

Bubbaba, I don't know anything about ponds, but if you put in concrete at a thickness of 10 cm, which I don't think you would need it to be that thick, then you would need about 31.7 cubic metres of concrete and at 2,500 baht a cubic metre that is 79,250. Throw in a steel mesh mat, labour, and some inflation on the last time I bought ready-mix (2 years ago) and you should be able to do it for about 150,000 baht. This is Issan prices. Issangeorge

[bubbaba]

Bubbaba, I don't know anything about ponds, but if you put in concrete at a thickness of 10 cm, which I don't think you would need it to be that thick, then you would need about 31.7 cubic metres of concrete and at 2,500 baht a cubic metre that is 79,250. Throw in a steel mesh mat, labour, and some inflation on the last time I bought ready-mix (2 years ago) and you should be able to do it for about 150,000 baht. This is Issan prices. Issangeorge

Issangeorge. Thank you for the information. That's about what I figured. But not what contractors want to figure.

[allcladrad]

Have you considered just digging a hole and using a liner? Much cheaper, the edge can be covered and made to appear natural. It could be pumped for cleaning between crops, a thought. About half of the Thais around me use them.

[bubbaba]

Yes, I have thought of using a linner, but, I worry abut it leaking, not lasting long and so forth. I know less about using a liner then I do cement. Can you or anyone provide more informaation? Reliable contractor who could do the job, estimated costs, etc. Step by step procedures for D-I-yourself. Any contact's in or around Korat?

All of my family and their friends have cement on the brain. They just shake their heads and laugh when I say anything other then cement. They just dont like and know about pond liners so, I really need help from outside the family circle.

I am digging now, slowly, but I still am in the planning, thinking stage and I really know nothing about this subject of ponds, at least from this angle. I can hold my own standing on the bank with a rod in my hand, but that's the other side of the coin. I appreciate any and all information. Thank you.

[allcladrad]

Yes, I have thought of using a linner, but, I worry abut it leaking, not lasting long and so forth. I know less about using a liner then I do cement. Can you or anyone provide more informaation? Reliable contractor who could do the job, estimated costs, etc. Step by step procedures for D-I-yourself. Any contact's in or around Korat?

All of my family and their friends have cement on the brain. They just shake their heads and laugh when I say anything other then cement. They just dont like and know about pond liners so, I really need help from outside the family circle.

I am digging now, slowly, but I still am in the planning, thinking stage and I really know nothing about this subject of ponds, at least from this angle. I can hold my own standing on the bank with a rod in my hand, but that's the other side of the coin. I appreciate any and all information. Thank you.

I am not knowledgeable about your area, would guess that if you have any aquaculture in you neighborhood they can help. Also concrete leaks as well and anything.

The liners are fairly thick and are overlapped at the seems.

Usually when someone is dead set against something they either have expericence or not, family is usually in the not group. The expense of concrete is formitable, then you have a needs to know what they are doing person to do the project.

With the liner you have a larger margin for error and can do the project with manual labor, no expert involved.

The concrete around my pond is a constant maintenance problem.

Do some internet searches regarding pond liner and I think you may pick up some confidence.

The online examples I have seen are easy to understand and will only need to be enlarged to fit your needs.

Finally a concrete pond is less than attractive.

I would access my goals, what is it you are trying to accomplish? How much do you want to spend and how committed to the project are you? Ponds are a fairly large responsibility, if you decide to give it up how will you accomplish that?

[rice555]

Hello bubbaba, for some info try, http://www.everliner.com/ The 2 places I've seen liners in Korat is a outside restaurant's pond, on Sub Suri Rd 47 on the L/H side of See-lee furniture store. Some boys in brown owned the place. We talked to one of the wife's when we ate there and she said that they got the liner in Korat, this was 5 years back.

The place if you want to check, is one on the road, one block from the Hwy coming into Korat behind the place the make the buses before the overpass over the RR tracks. The second place is going from the Hwy into Pac Chong. HUGE holding ponds for back flow to the electric generating unit at the dam.

Eksuwan Kaset (2001) Co. LTD 241/11 Moo 17 Kanchanapisek Rd. Salathammasop, Taveewatana BKK 10170 # 0-2448-0327, fax -2448-0968 @[email protected] has had a picture of pond liners in their ad in House Agriculture Magazine for 5-6 years now. In downtown Korat, you may try BMC 044-269-444, it's a Thai version of an big Ace Hardware store, they may be able to order or know if someone local who does. It's across the street from the "tallest" building in town(with a crane on it) 2 blocks from the north moat. Big Wat across the street from the other entrance. The #8 songtao goes by it.

rice555

[bubbaba]

While searching for information today, I got into a conversation with an American who has lived here over 20 years. I want to put what I heard/learned today on here so I can get the opinion, comments, whatever from others on this forum. When I see, talk with this man again, I will get more information and post it here.. He is to talk with my Thai family member who may build my pond.

Flexable concret?? Large cement pond built with no re-bar?? I ask him why so many falang build ponds here that failed.

He said because we stick to our ways of building back home and not the Thai way. He also said that the cement mix and cement here is different then our countries. The cement here will give/flex and not break or crack because of the type of cement and the way they mix it here.

To build my pond he said to excavate to size. Then to lay down a plastic layer like the one that the Thai road builders use here for the highways. On top of this to lay loose concret blocks. They could be mortered if I wanted but not necessary. Over this he said to pour cement, a 1, 2, 3, Thai mix with "any seeping" waterproofing mixed in. The pond will not leak and should last for 30 to 50 years with no problems.

He said that iron re-bar and screen wire that is sometimes used would rust over time and the pond shell would fail. In the US the cement covers and protects the iron so that it does not rust, but, here water will get to it in a pond.

For sure I don't know.

[chownah]

I'm a civil engineer. I've mixed alot of concrete myself in building my house here in Thailand. There is no special Thai way of mixing concrete that I have seen. Flexible concrete that doesn't crack or break just ain't going to happen at least I have never heard of it and really can't imaging how it would work without possibly some really high tech additives that I've never heard of (and probably don't exist) and I don't think that 1-2-3 mix with water proofer is going to be flexible and not break or crack...I don't see how this could be. I should qualify what I have said....ALL concrete is flexible to a degree...but ALL concrete is prone to cracking. It is possible to make a small piece of concrete that does not crack. Also, we are talking white concrete made with portland cement (and possibly with additives in the cement powder).....asphalt concrete (the black stuff used in making roads which is made using petroleum as the binder) is much more flexible than portland cement concrete but I don't think this is what your friend is talking about.

Ask your friend to describe exactly what is involved in making concrete the Thai way so that it is flexible and doesn't crack.....maybe I'll learn something new.

Chownah

[bubbaba]

Hi Chownah. Thanks. Your response is about what I expected. I don't know much about cement, but, I had never heard of cement that does not crack. Yes, He will be talking with my uncle(thai) who is a builder and maybe the one who will build my pool. My Thai wife will be in on that conversation so we will pick him good. It would be nice to get correct information but from him I am not sure.

What abut building without iron and his saying iron will rust away when used in Thailand? More nonesense?

[chownah]

Iron doesn't rust any faster in Thailand than anyplace else as far as I know. REbar placed in concrete that will be submerged should be covered by a thicker layer of concrete and the concrete should be mixed with the least amount of water possible and still be workable. I don't know how long rebar will last in submerged concrete........but properly constructed reinforced concrete swimming pools last a long time I think...and ferrocement boats do too. How long do the bases of reinforced concrete column last....many of them are pretty much submerged all of the time but they seem to last a long time too...I guess.

In Thailand rebar might rust faster because here the amount of concrete covering the rebar is not consistent and it is not uncommon to have some rebar right at the surface of the pour...this will allow rust to develop rather quickly....also the concrete is often mixed very lean (less cement and more sand and rock) which creates a more porous concrete and also usually alot of water is used in the mix to make placing easier and this also creates a more porous concrete......so.......it probably is that rebar rusts faster in Thailand but it is because of poor habits in design and construction.

Sorry I can't give a definite answer on how long rebar will last.....alot depends on the quality of the concrete and the amount of cover.

Chownah

[allcladrad]

I have to agree with Chownah, there is no magic here, in fact you may never know the mixture of your concrete, as the builder may be trying to save you money and use more sand or gravel and less cement or cut back on the rebar, he may be trying to save himself money and who knows where he will cut, could just be too lazy to go and buy the extra bag. The mixture is probably not the same in any case, varies from batch to batch, where one batch joins another is another area for possible trouble.

Cement blocks have holes in them and pouring concrete over them would seem to be asking for trouble from the resulting air gaps, putting the block on the plastic seems to be another recipe for failure. Unreinforced concrete is a set up for failure. Reinforced concrete has enough problems with out inviting more. The additives that I have seen used in concrete do improve the flex and the strength but they were used with rebar.

If I am not mistaken rust requires air plus moisture and when sealing in concrete eliminates the air.

A final note unless you are 100% lucky, water will find a way under your pond and as it does it will erode the earth that supports the concrete, which if unreinforced could crack or cave.

Again as Chownah mentioned, think about all of the concrete bridge supports and how long they have been under water.

[slapout]

Iron rebar is fairly new in Asian construction, they used bamboo strips for years, it works good if not in contact with soil after the concrete is poured. Rust of rebar is probably where it is exposed to weather. I would think any commonly used material for strength in concrete will be compromised if exposed to the weather here.

[chownah]

Iron rebar is fairly new in Asian construction, they used bamboo strips for years, it works good if not in contact with soil after the concrete is poured. Rust of rebar is probably where it is exposed to weather. I would think any commonly used material for strength in concrete will be compromised if exposed to the weather here.

They still use bamboo strips sometimes.....when they paved our soi a few years ago they put bamboo strips in the concrete pavement....and sometimes people will put bamboo in to reinforce sidewalks around their houses.

Epoxy coated rebar is used in certain places on important bridges in the US to guarantee no rust or corrosion of the rebar....it is expensive so its not practical for use here but just thought I'd mention it.

Chownah

[Lickey]

If the family recreation/fish pond is made with a concrete liner, would it need some kind of sealer/resin over the concrete? to stop the toxins in the cement affecting the fish ect, same as a public swimming pool? so perhaps you would need a recircorlatory pumping system too with filters ect, and some shaded areas, be careful what you plant, your pond could soon be full of dead leaves ect, and wind-blown dust will make the water murky yellow brown.

So perhaps have a 2 level pond, the top one about 5mtrs sq with a water feature, rocks with a waterfall for the family,overflowing into the main fish pool, all sorts of connatations to think about, Cheers, Lickey..

[phibunmike]

Iron rebar is fairly new in Asian construction, they used bamboo strips for years, it works good if not in contact with soil after the concrete is poured. Rust of rebar is probably where it is exposed to weather. I would think any commonly used material for strength in concrete will be compromised if exposed to the weather here.

I know nothing about concrete, but I have read about fibres which can be mixed in instead of using re-bar. Supposedly this gives a stronger result less prone to hairline cracking, and especially good for pools and ponds. Does anyone know what fibres are used, where to buy them, and how effective they are?

Cheers,

Mike

[ozzydom]

Bubbaba ,what soil type do you have to work with that you say wont hold water and are there any clay based soils in your area

Ozzy

[chownah]

Iron rebar is fairly new in Asian construction, they used bamboo strips for years, it works good if not in contact with soil after the concrete is poured. Rust of rebar is probably where it is exposed to weather. I would think any commonly used material for strength in concrete will be compromised if exposed to the weather here.

I know nothing about concrete, but I have read about fibres which can be mixed in instead of using re-bar. Supposedly this gives a stronger result less prone to hairline cracking, and especially good for pools and ponds. Does anyone know what fibres are used, where to buy them, and how effective they are?

Cheers,

Mike

Try googling "fiber reinforced concrete".

Chownah

[bubbaba]

Bubbaba ,what soil type do you have to work with that you say wont hold water and are there any clay based soils in your area

Ozzy

I don't know. The top soil, approx. 15 inches is brown. Looks like all silt. Very dry and dusty. Maybe some sand in there. Below that is what I call clay. Reddish orange color and hard as a rock when dry. Not to bad to dig in after a rain and a short draining period. Last October it rained every day very hard for 30 plus days. The pond hole filled up about 2 feet of water during that time. Ten days to 2 weeks later the water was gone. When it rains hard for one day here it only takes about one hour and the water is gone. I plan to stir some soil into a glass of water and let it sit for an hour or so. I plan to do this with both of the above soils. That will give me a rough idea of what type of soil I have. I plan to do this tomorrow. Then I will let you know what I come up with. I live 13 kilometers outside of Korat. Visitors welcome. Help welcome.

[nahkbin]

Bubbaba ,what soil type do you have to work with that you say wont hold water and are there any clay based soils in your area

Ozzy

I don't know. The top soil, approx. 15 inches is brown. Looks like all silt. Very dry and dusty. Maybe some sand in there. Below that is what I call clay. Reddish orange color and hard as a rock when dry. Not to bad to dig in after a rain and a short draining period. Last October it rained every day very hard for 30 plus days. The pond hole filled up about 2 feet of water during that time. Ten days to 2 weeks later the water was gone. When it rains hard for one day here it only takes about one hour and the water is gone. I plan to stir some soil into a glass of water and let it sit for an hour or so. I plan to do this with both of the above soils. That will give me a rough idea of what type of soil I have. I plan to do this tomorrow. Then I will let you know what I come up with. I live 13 kilometers outside of Korat. Visitors welcome. Help welcome.

The deal about rebar rusting. One of the problems with old bridges in Florida was that the concrete contained salt which attacked the rebar and just sort of dissolved it over the years. Seems to me that I read that most cement contains some sodium. Lots of sand contains salt also. Re enforced concrete is the way to go. Thick PVC liners work but are too slippery when they get just a bit of algae on them.j Definitely no concrete blocks or clay bricks. I have been there and been through that.

Another problem that I have seen here in Thailand is the failure of the contractor/builder to get the edges of the pond level. Be careful of run off into the pond.

nahkbin

[phibunmike]

Iron rebar is fairly new in Asian construction, they used bamboo strips for years, it works good if not in contact with soil after the concrete is poured. Rust of rebar is probably where it is exposed to weather. I would think any commonly used material for strength in concrete will be compromised if exposed to the weather here.

I know nothing about concrete, but I have read about fibres which can be mixed in instead of using re-bar. Supposedly this gives a stronger result less prone to hairline cracking, and especially good for pools and ponds. Does anyone know what fibres are used, where to buy them, and how effective they are?

Cheers,

Mike

Try googling "fiber reinforced concrete".

Chownah

Thank you Chownah. So there are various types of fibre.

Does anyone know where (and how) to buy them (in Thailand), if they are widely available and used here (do local builders know what to do with them), and has anyone had experience using them on ponds here.

Thanks,

Mike

[johnh101]

Sulphur Resistant Portland Cement is the norm for maritime usage.

[ozzydom]

Bubbaba,It sounds like you have typical soil structure similar to what we have here between Udon and Sakhon Nakhon,We have four ponds totalling about four rai .The initial one was of similar design to yours and is not totally suitable for Pla Nin.

The other three were dug by tractor only with depth sloping from one to one and a half metres.

Pla Nin spend most of their time in the top 50cm so to much depth is useless as its to dark for phytoplankton to multiply and it just becomes a smelly sump of ammonia.

The clay based soil is like a sponge, it will only hold so much water until saturated then holds status quo,in other words after the initial saturation it virtually self seals .

Two ends of our ponds are just big bung walls as our water level is about six feet above the surrounding paddies,to alleviate leakage there ,we laid the cheap black polythene sheeting in about the centre of the walls then built the internal slope over the plastic to a 4to 1 angle.

We have about 4 rai surface area and only need to top up once a fortnight ,we only need to run the 3"pump for one day to top up all ponds as we only lose about 1inch a week through soakage and evaporation.

I will pm you some photos in the next day or two which may be of interest.

ozzy

[chownah]

Sulphur Resistant Portland Cement is the norm for maritime usage.

Does "maritime" indicate salt water?

Chownah

[ozzydom]

I'm a civil engineer. I've mixed alot of concrete myself in building my house here in Thailand. There is no special Thai way of mixing concrete that I have seen. Flexible concrete that doesn't crack or break just ain't going to happen at least I have never heard of it and really can't imaging how it would work without possibly some really high tech additives that I've never heard of (and probably don't exist) and I don't think that 1-2-3 mix with water proofer is going to be flexible and not break or crack...I don't see how this could be. I should qualify what I have said....ALL concrete is flexible to a degree...but ALL concrete is prone to cracking. It is possible to make a small piece of concrete that does not crack. Also, we are talking white concrete made with portland cement (and possibly with additives in the cement powder).....asphalt concrete (the black stuff used in making roads which is made using petroleum as the binder) is much more flexible than portland cement concrete but I don't think this is what your friend is talking about.

Ask your friend to describe exactly what is involved in making concrete the Thai way so that it is flexible and doesn't crack.....maybe I'll learn something new.

Chownah

As a professed civil engineer I would hope you are referring to the cracking of the plaster (render ) finish of concrete and not cracking of the main structures or slabs, cracking of main sections of a structure is the pathway to condemnation and demolishment.

All concrete structures are designed with expansion and contraction points to prevent damage to structures.

A recent case in point was the millions spent X-raying sections of the new Bankok Airport buildings after cracks appeared,to ascertain whether it was surface cracking or serious structural damage.

Cracking serious enough to allow the passage of moisture and air is a recipe for disaster as this allows rusting of reinforcing steel and subsequent growth of the steel which in turn destroys the concrete from the inside..

[brahmburgers]

a pond for cement fish?

I would think such fish would be hard to cut with a knife - and difficult to digest.

[chownah]

I'm a civil engineer. I've mixed alot of concrete myself in building my house here in Thailand. There is no special Thai way of mixing concrete that I have seen. Flexible concrete that doesn't crack or break just ain't going to happen at least I have never heard of it and really can't imaging how it would work without possibly some really high tech additives that I've never heard of (and probably don't exist) and I don't think that 1-2-3 mix with water proofer is going to be flexible and not break or crack...I don't see how this could be. I should qualify what I have said....ALL concrete is flexible to a degree...but ALL concrete is prone to cracking. It is possible to make a small piece of concrete that does not crack. Also, we are talking white concrete made with portland cement (and possibly with additives in the cement powder).....asphalt concrete (the black stuff used in making roads which is made using petroleum as the binder) is much more flexible than portland cement concrete but I don't think this is what your friend is talking about.

Ask your friend to describe exactly what is involved in making concrete the Thai way so that it is flexible and doesn't crack.....maybe I'll learn something new.

Chownah

As a professed civil engineer I would hope you are referring to the cracking of the plaster (render ) finish of concrete and not cracking of the main structures or slabs, cracking of main sections of a structure is the pathway to condemnation and demolishment.

All concrete structures are designed with expansion and contraction points to prevent damage to structures.

A recent case in point was the millions spent X-raying sections of the new Bankok Airport buildings after cracks appeared,to ascertain whether it was surface cracking or serious structural damage.

Cracking serious enough to allow the passage of moisture and air is a recipe for disaster as this allows rusting of reinforcing steel and subsequent growth of the steel which in turn destroys the concrete from the inside..

When I studied concrete design at University they taught us that any piece of concrete big enough to be a part of a structure would crack eventually....I believe that the major cause of this is temperature differentials but I can't remember for sure. The idea in concrete design is that rebar is placed in the concrete so that when the concrete cracks the cracks are held tightly closed by the rebar. In a properly reinforced piece of concrete the cracks will not be visible. Bottom line is that we were taught that basically all concrete will crack with time and rebar must be placed to hold the cracks together. In construction in the US an on grade (built on compacted earth) concrete floor slab is usually thick enough to support the required load but light reinforcing steel will be place one foot on center in both directions and this steel is called "temperature steel". It is called this because temperature differentials will eventually cause the slab to crack and the steel will hold the cracks tightly closed to limit infiltration of air and water...and to prevent slippage along the crack which would abrade the crack which would enlarge it.

Also, I do profess to be a civil engineer in that I am a licensed professional engineer in the US....although I am a few years behind in paying my licensing fees!!!!!!!

Chownah

Edited January 7, 2008 by chownah

[johnh101]

Sulphur Resistant Portland Cement is the norm for maritime usage.

Does "maritime" indicate salt water?

Chownah

Normally yes, but it would also be used normally in rivers and estuaries. The water here has a high salts content so I would try and see if it was available before I used anything else.

[chownah]

Sulphur Resistant Portland Cement is the norm for maritime usage.

Does "maritime" indicate salt water?

Chownah

Normally yes, but it would also be used normally in rivers and estuaries. The water here has a high salts content so I would try and see if it was available before I used anything else.

I guess this is probably especially true in Isaan since many regions there have very salty ground water...I'm interested in learning more...do you have an internet link?