I do not think of my self as a know all about pond building but I have built a few now and have put together a bit of a run down on my last one there has been a few questions raced and I am grateful of any feedback good or bad if anything the calculation for the pond liner might help.
Building a simple square Koi pond
Using a liner not a performed pond.
A fibreglass Pond Liner is the most common type of pre-formed Pond Liner. Pre-cast fibreglass/plastic ponds are available in garden centre and aquatic centres. While they are the most durable of Pond Liners, on the flip side, they tend to be less attractive, more expensive and more difficult to conceal than flexible Pond Liners. My first choice is always the pond liner.
I have found building a concrete ring to make the outside walls and plant shelves this helps stabilizes and level the adjacent soil. Even if you think your dirt is really firm, it may shift easily when wet. There is nothing worse than seeing a pond wall collapse after a heavy rain, or if people walk to close to the edge. The easiest is to dig a trench 2ft wide by 1ft deep around the perimeter of the pond. Then you fill this with concrete, forming a solid concrete ring around the perimeter. The dirt is then dug out from inside this ring. Others use concrete blocks to line the inside walls of the pond. I used treated timber to make my shuttering. I then covered the bottom with sand and a special underlay bought from my local Aquatic centre. Rather than using heavy sand, which stones and roots can penetrate, it is essential to use underlay with all liners. Underlay is made from a woven material which is rot resistant and extremely difficult for sharp objects and roots to penetrate. Using an underlay should ensure that you have no surprise holes appearing in your liner, requiring awkward repairs or expensive replacement. Then I used a pond liner over the sand and underlay. There are loads of liners on the market from cheap to very expensive Butyl is a premium, synthetic rubber pond liner recommended by leading European water gardening experts If you want your pond for a long time I would get this. The one I have has a guarantee for 35 years. Liners are available in .75mm and 1mm thicknesses. Particularly those smaller than 1,500 sq. ft, should be lined with .75nn Butyl. You can use PVC this is another alternative but I would stick with the Butyl.
.To calculate the size of pond liner proceed as follows:-
Length of liner = twice maximum depth of pond + maximum length of pond + 1m (3' 3") excess.
Width of liner = twice maximum depth of pond + maximum width of pond + 1m (3' 3") excess.
When fitting liner Make sure that the weather is relatively warm as the liner will be more flexible. Lay it centrally across, try to not get any folds that could trap dirt and fish in corners and fill the water will pull the liner tight. Leave the water and liner to settle. Trim excess liner, leaving at least 6" all the way round.
Filtration:
You must first understand that you should have at least a hundred gallons more filtration than actual pond water. This is because although the filter might say that it will work on a pond (lets say) 1400 Gallons, if you pond was 1375 gallons then the 1400 gallon filter would be struggling to work flat out to keep it clean. You can never over filter a pond - so make sure the filter you choose is adequate. If you intend to have a highly stocked Koi pond then you should aim to have a filter to cope with one and a half times the capacity of the water in your pond.
Building a simple square Koi pond
Using a liner not a performed pond.
A fibreglass Pond Liner is the most common type of pre-formed Pond Liner. Pre-cast fibreglass/plastic ponds are available in garden centre and aquatic centres. While they are the most durable of Pond Liners, on the flip side, they tend to be less attractive, more expensive and more difficult to conceal than flexible Pond Liners. My first choice is always the pond liner.
I have found building a concrete ring to make the outside walls and plant shelves this helps stabilizes and level the adjacent soil. Even if you think your dirt is really firm, it may shift easily when wet. There is nothing worse than seeing a pond wall collapse after a heavy rain, or if people walk to close to the edge. The easiest is to dig a trench 2ft wide by 1ft deep around the perimeter of the pond. Then you fill this with concrete, forming a solid concrete ring around the perimeter. The dirt is then dug out from inside this ring. Others use concrete blocks to line the inside walls of the pond. I used treated timber to make my shuttering. I then covered the bottom with sand and a special underlay bought from my local Aquatic centre. Rather than using heavy sand, which stones and roots can penetrate, it is essential to use underlay with all liners. Underlay is made from a woven material which is rot resistant and extremely difficult for sharp objects and roots to penetrate. Using an underlay should ensure that you have no surprise holes appearing in your liner, requiring awkward repairs or expensive replacement. Then I used a pond liner over the sand and underlay. There are loads of liners on the market from cheap to very expensive Butyl is a premium, synthetic rubber pond liner recommended by leading European water gardening experts If you want your pond for a long time I would get this. The one I have has a guarantee for 35 years. Liners are available in .75mm and 1mm thicknesses. Particularly those smaller than 1,500 sq. ft, should be lined with .75nn Butyl. You can use PVC this is another alternative but I would stick with the Butyl.
.To calculate the size of pond liner proceed as follows:-
Length of liner = twice maximum depth of pond + maximum length of pond + 1m (3' 3") excess.
Width of liner = twice maximum depth of pond + maximum width of pond + 1m (3' 3") excess.
When fitting liner Make sure that the weather is relatively warm as the liner will be more flexible. Lay it centrally across, try to not get any folds that could trap dirt and fish in corners and fill the water will pull the liner tight. Leave the water and liner to settle. Trim excess liner, leaving at least 6" all the way round.
Filtration:
You must first understand that you should have at least a hundred gallons more filtration than actual pond water. This is because although the filter might say that it will work on a pond (lets say) 1400 Gallons, if you pond was 1375 gallons then the 1400 gallon filter would be struggling to work flat out to keep it clean. You can never over filter a pond - so make sure the filter you choose is adequate. If you intend to have a highly stocked Koi pond then you should aim to have a filter to cope with one and a half times the capacity of the water in your pond.
