Creating a garden pond
 
By Adrian Thomas with further material by Ian Thornhill.         Reviewed by Steve Head
 
Ponds are arguably the richest, most productive and engaging of all wildlife habitats in the garden, hosting a range of wildlife that otherwise struggle to find a home there. Even a small garden pond is likely to be colonised by some small invertebrates, and one that is medium-sized is likely to be busy in spring and summer with frogs, newts and a selection of the commoner damselfly and dragonfly species.
 
While we may have a good idea of what creatures can be found in garden ponds, there is still much detail we don't know and much assumption and, from some sources, contradiction about what makes a good wildlife pond.
 
Creating a garden pond from scratch means quite a lot of work. Garden ponds have also had a major role in the spread of invasive aquatic plants, and ponds can pose safety issues for young children. For these reasons, while creating a garden pond is definitely something that should be considered by every gardener, it should be done with care and planning.
 
Emperor dragonfly laying eggs in a garden pond
Shape: Many wildlife gardening texts recommend that a pond should have wavy margins, and from the aesthetic point of view, such ponds appear more "natural".  Irregular outlines help increase the effective circumference of the pond, and hence the extent of shallow-water marginal habitats.  It is likely that these will indeed help increase the number of micro-environments, but they can also be created effectively in straight-margined ponds by using the topography within the pond. There is no evidence to say that a well-designed, straight-sided pond cannot be as good for wildlife as a wavy-edged one.
 
Depth: Many older books recommend a minimum centre-pond depth of at least 60cm. However, the Freshwater Habitats Trust points out that this advice originated from fish-keeping and that most invertebrate wildlife needs shallow rather than deep water. They suggest that the deepest area need not be greater than 30cm. In contrast, the National Amphibian Survey concluded that amphibians (except frogs) were found less frequently in ponds less than 0.5m deep.
 
Deep ponds don't look very different aesthetically from shallower ponds, so appearance isn't a factor.  One big problem with deeper ponds is that they are more likely to suffer with low summer oxygen levels at the bottom, especially if the pond gets a lot of leaf debris falling in suring the autumn.  At worst the pond can go anoxic and smelly when disturbed, probably requiring a sludge pump.
 
So probably the most important advice is not to go for a very deep pond (and this will save a lot of digging) but to concentrate on its topography and make the bed of the pond to be as gently shelving as possible - steep-sided ponds are likely to offer the fewest opportunities for wildlife. If you can add undulations and irregularities in the bed, so much the better. Given that most biodiversity is in the vegetation at the margins, concentrating on this makes sense
 
Location: The most important decision regarding location is to make sure you will not encounter any services when digging (eg electricity cables, water, sewage and gas pipes).  These are not often found in back gardens, but check your deeds for any information, and look to see whjere the services enter your house.  Manhole covers are the give-away for sewerage.  If in doubt you can hire a piece of kit called a Cable Avoidance Tool which can locate electric, telephone and metal gas or water pipes.
 
Shade:  The other regular advice is not to place ponds in shade. Certainly heavy shade can inhibit amphibians, but equally other creatures including most amphibians prefer some shade.  A mixture of sun and shade allows animals to move to cooler or warmer water as it suits them.
 
However, ponds directly under trees are l prone to leaf litter falling in. So while 'Ponds should not be shaded by trees' is one of the pond myths identified by Biggs et al (1994)*, most gardeners are likely to opt for a sunnier pond not overhung with branches. Another good reason to do this is to avoid damaging the roots of established trees while digging the pond. If your pond will be overhung by trees, it is best to keep it shallow, or accumulated dead leaves in deeper water can decay and cause anoxic conditions limiting bottom life.  The alternative is to net the surface off in autumn and try to catch the leaves before they fall in.  Most of us forget to do this until too late.
 
*(New Approaches to the Management of Ponds. Biggs, J. Corfield, A., Walker, D.,  Whitfield, M. & Williams, P. In British Wildlife, 1994  Vol 5, 273-287)
 
Creating a garden pond
 
By Adrian Thomas with further material by Ian Thornhill.  
Reviewed by Steve Head
 
Ponds are arguably the richest, most productive and engaging of all wildlife habitats in the garden, hosting a range of wildlife that otherwise struggle to find a home there. Even a small garden pond is likely to be colonised by some small invertebrates, and one that is medium-sized is likely to be busy in spring and summer with frogs, newts and a selection of the commoner damselfly and dragonfly species.
 
While we may have a good idea of what creatures can be found in garden ponds, there is still much detail we don't know and much assumption and, from some sources, contradiction about what makes a good wildlife pond.
 
Creating a garden pond from scratch means quite a lot of work. Garden ponds have also had a major role in the spread of invasive aquatic plants, and ponds can pose safety issues for youn children. For these reasons, while creating a garden pond is definitely something that should be considered by every gardener, it should be done with care and planning.
 
Raised ponds: Ponds that are constructed within architectural raised walls or sleepers are very fashionable and can always be seen at Smart Flower Shows. "Infinity ponds" are a particularly trendy type, where the pond edges are absolutely horizontal and precise, and the water comes to the very top, forming a perfect reflective surface.  Such ponds may even have seating in an inner sunken dry area, a sort of inverse island.  The trouble is that while they look amazing at Chelsea, in practice they can fill with blanketweed unless chlorinated, and leaves, insects and other rubbish accumulates at the edge and completely spoils the look.  They aren't wildlife ponds.
 
Raised ponds are accessable for flying insects, and they make pond-dipping easier and safer for children, but they pose a major challenge to any terrestrial creature trying to get in or out.
 
Good wildlife ponds should merge seamlessly with the terrestrial habitat in which they are placed, so raised ponds really don't cut the mustard!
 
 
This pond was made from a redundant swimming pool that the owner (Steve Head) couldn't afford to maintain.  The empty pool sides were broken down, and the hole made a handy skip during renovation work on the house. The edges were landscaped, and a butyl liner was fitted.  It is filled using pumped well-water; unfortunately the water table contains fertilisers from farming, and the pond is prone to blanketweed.
 
Planting the Norfolk reed (Phalaris arundinacea) proved a big mistake, in three years it practically covered the near-end of the pond. The tall dense plant at the far end is Japanese horsetail (Equisetum ramosissimum var. japonicum) which was beautiful, but incredibly invasive and has taken 4 years to (nearly) eradicate!
Pond construction and materials
 
There are many websites that will give more detailed instructions on how to create a pond. The key factors to consider are time, money and effort!  Creating a medium-sized pond is a big job, and could cost several hundred pounds to be done well. Skimp, and you may end up with a sub-standard pond that leaks.  For helpful details on positioning, digging and establishing a pond see our leaflet Placing and constructing a garden pond by Ian Thornhill.
 
Other well illustrated website guides on pond construction we recommend:
 
Freshwater Habitats Trust   Written by the top UK pond ecologists
Wild about gardens website  - but we don't recommend adding soil into the pond.
Royal Horticultural Society   Look at pages coming from this link
Froglife's "Just add water"   A substantial but readable guide
British Dragonfly Society     Aimed especially at dragonflies
 
 
Resources available from this page:
Ponds and the law
To have fish or not?
Placing and constructing a garden pond
 
 
Download our How-to guides:
 
How to: Bring water into your garden
How to: Make a pond in a pot
How to: Create and maintain ponds for wildlife
This is an interesting pond designed rather cleverly as a combination of an architectural feature and a wildlife pond. It has a stark decking surround and wooden margins on three sides, but shelves pleasingly on the third.
 
This pond could have developed nicely with judicious planting, but is dead and sterile because the designer used anti-rot tanalised timber, which leaks toxins into the water killing plants and animals alike.
 
Until 2006 tanalising mixes used chromium and arsenic as ingredients, although now they has been removed leaving copper and triazole biocides, both designed to kill wood borers and fungi.
 
Nowadays, there are much better options, especially the use of recycled plastic which is inert and doesn't look too bad either.
 
Above:  This pond was made from a redundant swimming pool that the owner (Steve Head) couldn't afford to maintain.  The empty pool sides were broken down, and the hole made a handy skip during renovation work on the house. The edges were landscaped, and a butyl liner was fitted.  It is filled using pumped well-water; unfortunately the water table contains fertilisers from farming, and the pond is prone to blanketweed.
 
Planting the Norfolk reed (Phalaris arundinacea) proved a big mistake, in three years it practically covered the near-end of the pond. The tall dense plant at the far end is Japanese horsetail (Equisetum ramosissimum var. japonicum) which was beautiful, but incredibly invasive and has taken 4 years to (nearly) eradicate!
 
Key principles for garden ponds
 
Size: There is much encouragement in books to put a pond into a garden irrespective of the surface area or volume of water. Certainly the Common Frog will spawn in quite small waterbodies, but be prepared that tiny ponds may have limited wildlife interest. Also, the smaller the pond, the more difficult it is likely to be to maintain water quality.
 
Most pond creatures probably have an instinctive sense of the minimum surface area they require - for example, the British Dragonfly Society recommends that the minimum size of a viable pond for dragonflies and damselflies is about 4 sq. m (43 sq. ft), but some species need much more. More study on this would be welcome.
 
So although "the bigger the pond, the better" was one of the myths identified by Biggs et al in 1994*, it may actually be true in a garden setting. In the absence of further research, the best advice currently is probably the British Dragonfly Society's: "For maximum effect, aim for the largest pond you can afford and your garden can accommodate".
 
*(New Approaches to the Management of Ponds. Biggs, J. Corfield, A., Walker, D.,  Whitfield, M. & Williams, P. In British Wildlife, 1994  Vol 5, 273-287)
 
Above: Emperor dragonfly laying eggs in a garden pond
 
Shape: Many wildlife gardening texts recommend that a pond should have wavy margins, and from the aesthetic point of view, such ponds appear more "natural".  Irregular outlines help increase the effective circumference of the pond, and hence the extent of shallow-water marginal habitats.  It is likely that these will indeed help increase the number of micro-environments, but they can also be created effectively in straight-margined ponds by using the topography within the pond. There is no evidence to say that a well-designed, straight-sided pond cannot be as good for wildlife as a wavy-edged one.
 
Depth: Many older books recommend a minimum centre-pond depth of at least 60cm. However, the Freshwater Habitats Trust points out that this advice originated from fish-keeping and that most invertebrate wildlife needs shallow rather than deep water. They suggest that the deepest area need not be greater than 30cm. In contrast, the National Amphibian Survey concluded that amphibians (except frogs) were found less frequently in ponds less than 0.5m deep.
 
Deep ponds don't look very different aesthetically from shallower ponds, so appearance isn't a factor.  One big problem with deeper ponds is that they are more likely to suffer with low summer oxygen levels at the bottom, especially if the pond gets a lot of leaf debris falling in suring the autumn.  At worst the pond can go anoxic and smelly when disturbed, probably requiring a sludge pump.
 
So probably the most important advice is not to go for a very deep pond (and this will save a lot of digging) but to concentrate on its topography and make the bed of the pond to be as gently shelving as possible - steep-sided ponds are likely to offer the fewest opportunities for wildlife. If you can add undulations and irregularities in the bed, so much the better. Given that most biodiversity is in the vegetation at the margins, concentrating on this makes sense
 
Location: The most important decision regarding location is to make sure you will not encounter any services when digging (eg electricity cables, water, sewage and gas pipes).  These are not often found in back gardens, but check your deeds for any information, and look to see whjere the services enter your house.  Manhole covers are the give-away for sewerage.  If in doubt you can hire a piece of kit called a Cable Avoidance Tool which can locate electric, telephone and metal gas or water pipes.
 
Shade:  The other regular advice is not to place ponds in shade. Certainly heavy shade can inhibit amphibians, but equally other creatures including most amphibians prefer some shade.  A mixture of sun and shade allows animals to move to cooler or warmer water as it suits them.
 
However, ponds directly under trees are prone to leaf litter falling in. So while 'Ponds should not be shaded by trees' is one of the pond myths identified by Biggs et al (1994)*, most gardeners are likely to opt for a sunnier pond not overhung with branches. Another good reason to do this is to avoid damaging the roots of established trees while digging the pond. If your pond will be overhung by trees, it is best to keep it shallow, or accumulated dead leaves in deeper water can decay and cause anoxic conditions limiting bottom life.  The alternative is to net the surface off in autumn and try to catch the leaves before they fall in.  Most of us forget to do this until too late.
 
*(New Approaches to the Management of Ponds. Biggs, J. Corfield, A., Walker, D.,  Whitfield, M. & Williams, P. In British Wildlife, 1994  Vol 5, 273-287)
 
Shape: Many wildlife gardening texts recommend that a pond should have wavy margins, and from the aesthetic point of view, such ponds appear more "natural".  Irregular outlines help increase the effective circumference of the pond, and hence the extent of shallow-water marginal habitats.  It is likely that these will indeed help increase the number of micro-environments, but they can also be created effectively in straight-margined ponds by using the topography within the pond. There is no evidence to say that a well-designed, straight-sided pond cannot be as good for wildlife as a wavy-edged one.
 
Depth: Many older books recommend a minimum centre-pond depth of at least 60cm. However, the Freshwater Habitats Trust points out that this advice originated from fish-keeping and that most invertebrate wildlife needs shallow rather than deep water. They suggest that the deepest area need not be greater than 30cm. In contrast, the National Amphibian Survey concluded that amphibians (except frogs) were found less frequently in ponds less than 0.5m deep.
 
Deep ponds don't look very different aesthetically from shallower ponds, so appearance isn't a factor.  One big problem with deeper ponds is that they are more likely to suffer with low summer oxygen levels at the bottom, especially if the pond gets a lot of leaf debris falling in suring the autumn.  At worst the pond can go anoxic and smelly when disturbed, probably requiring a sludge pump.
 
So probably the most important advice is not to go for a very deep pond (and this will save a lot of digging) but to concentrate on its topography and make the bed of the pond to be as gently shelving as possible - steep-sided ponds are likely to offer the fewest opportunities for wildlife. If you can add undulations and irregularities in the bed, so much the better. Given that most biodiversity is in the vegetation at the margins, concentrating on this makes sense
 
Location: The most important decision regarding location is to make sure you will not encounter any services when digging (eg electricity cables, water, sewage and gas pipes).  These are not often found in back gardens, but check your deeds for any information, and look to see where the services enter your house.  Manhole covers are the give-away for sewerage.  If in doubt you can hire a piece of kit called a Cable Avoidance Tool which can locate electric, telephone and metal gas or water pipes.
 
Shade:  The other regular advice is not to place ponds in shade. Certainly heavy shade can inhibit amphibians, but equally other creatures including most amphibians prefer some shade.  A mixture of sun and shade allows animals to move to cooler or warmer water as it suits them.
 
However, ponds directly under trees are prone to leaf litter falling in. So while 'Ponds should not be shaded by trees' is one of the pond myths identified by Biggs et al (1994)*, most gardeners are likely to opt for a sunnier pond not overhung with branches. Another good reason to do this is to avoid damaging the roots of established trees while digging the pond. If your pond will be overhung by trees, it is best to keep it shallow, or accumulated dead leaves in deeper water can decay and cause anoxic conditions limiting bottom life.  The alternative is to net the surface off in autumn and try to catch the leaves before they fall in.  Most of us forget to do this until too late.
 
*(New Approaches to the Management of Ponds. Biggs, J. Corfield, A., Walker, D.,  Whitfield, M. & Williams, P. In British Wildlife, 1994  Vol 5, 273-287)
 
Key principles for garden ponds
 
Size: There is much encouragement in books to put a pond into a garden irrespective of the surface area or volume of water. Certainly the Common Frog will spawn in quite small waterbodies, but be prepared that tiny ponds may have limited wildlife interest. Also, the smaller the pond, the more difficult it is likely to be to maintain water quality.
 
Most pond creatures probably have an instinctive sense of the minimum surface area they require - for example, the British Dragonfly Society recommends that the minimum size of a viable pond for dragonflies and damselflies is about 4 sq. m (43 sq. ft), but some species need much more. More study on this would be welcome.
 
So although "the bigger the pond, the better" was one of the myths identified by Biggs et al in 1994*, it may actually be true in a garden setting. In the absence of further research, the best advice currently is probably the British Dragonfly Society's: "For maximum effect, aim for the largest pond you can afford and your garden can accommodate".
 
*(New Approaches to the Management of Ponds. Biggs, J. Corfield, A., Walker, D.,  Whitfield, M. & Williams, P. In British Wildlife, 1994  Vol 5, 273-287)
Raised ponds: Ponds that are constructed within architectural raised walls or sleepers are very fashionable and can always be seen at Smart Flower Shows. "Infinity ponds" are a particularly trendy type, where the pond edges are absolutely horizontal and precise, and the water comes to the very top, forming a perfect reflective surface.  Such ponds may even have seating in an inner sunken dry area, a sort of inverse island.  The trouble is that while they look amazing at Chelsea, in practice they can fill with blanketweed unless chlorinated, and leaves, insects and other rubbish accumulates at the edge and completely spoils the look.  They aren't wildlife ponds.
 
Raised ponds are accessable for flying insects, and they make pond-dipping easier and safer for children, but they pose a major challenge to any terrestrial creature trying to get in or out.
 
Good wildlife ponds should merge seamlessly with the terrestrial habitat in which they are placed, so raised ponds really don't cut the mustard!
 
Wildlife access: It is vital that creatures can get into and out of the pond easily, whether they be pond creatures that can't climb well or land creature that might fall in. Gently sloping sides and strategically placed rocks and logs are generally adequate.
 
Water sources: Clean water is an essential component of a healthy wildlife pond. The best water to fill a pond is rainwater. Do not dam or divert any water course to direct water into your pond. Upstream, there may be all sorts of fertiliser and pollution coming into the water, and in times of high rainfall it may also bring in silt.  You may also need an abstraction licence.  Tap water and run-off from the garden often contain nutrients in the form of  nitrates and phosphates, which makes your pond more susceptible to algal blooms. Tap water also contains chlorine, although it naturally disappears over a few days. If at all possible, prevent run-off of water into the pond that has passed through fertilised soil.
 
Fish: Fish will eat much of the wildlife in a pond and their excreta will also add nutrients to the pond, increasing the risk of algal blooms. However, with carefully constructed shallows and refuges, it is not impossible for a pond to support both fish and wildlife. For more information see our leaflet Fish and garden ponds by Ian Thornhill
 
Importing pond life: It is generally advocated not to move either mud or pond creatures from pond to pond, even though it may seem the quick and easy route to introduce wildlife to a pond. Certainly do not move amphibians or their spawn, which can spread red-leg disease and chytrid disease. Unless very isolated, most new ponds will rapidly be colonised of their own accord by blown seeds, or through larvae or eggs carried on pond plants or the feet of birds. There are also legal restrictions for certain invasive species, see Ian Thornhill's leaflet Ponds and the law.
 
Bog gardens and rain gardens: Boggy, saturated ground hosts a range of plants and their associated wildlife even if there is no standing water. Bog gardens can be a good alternative to a pond if water safety is a major consideration. They form naturally where the ground has poor drainage or the water table is high, but can be mimicked by digging out a hole, lining with a pond liner that is spiked with a few drainage holes (you should aim to impede drainage, not stop it altogether), and refilling with the excavated soil.
 
Rain gardens are rather different from bog gardens in that they are low lying areas which have been designed and planted so as to absorb water into the underground strata rather than overwhelm the drainage systems. They are gaining in popularity, and if designed well could become an important element of wildlife gardening.
 
Bird baths: If the only water you have space for is a birdbath, it is still worth adding to your garden. The key principle is to create a 'shallow puddle on a pole'. Birds will often prefer to bathe or drink from a bird bath compared to a pond as it offers a better vantage point from where to keep watch for predators.
 
Temporary ponds: A pond does not have to hold water all year to be of value to wildlife - there can be considerable wildlife value in areas of the garden that are only wet for part of the year (usually the winter and spring). You may have such an area naturally in your garden - if so, consider retaining it 'as is' rather than trying to drain it or turn it into a permanent pond.
 
Safety: Even the shallowest of water can be dangerous for young children. Open, unguarded ponds are a real risk in a garden. Consider either securely fencing off a pond area so that children can't access unsupervised, having a grille fitted over the top, or restricting yourself to a bog garden until the children are older. The shallow water and gently sloping sides to a good wildlife pond should also help should anyone fall in. The Royal Society for the Prevention of Accidents is a good source of information about pond safety.
 
Chemicals in the garden: Fertiliser run-off from the garden to the pond is strongly to be avoided.  Many chemicals used in the garden, including fungicides and insecticides also harm pond organisms.
 
 
 
Raised pond in a public garden
Wildlife access: It is vital that creatures can get into and out of the pond easily, whether they be pond creatures that can't climb well or land creature that might fall in. Gently sloping sides and strategically placed rocks and logs are generally adequate.
 
Water sources: Clean water is an essential component of a healthy wildlife pond. The best water to fill a pond is rainwater. Do not dam or divert any water course to direct water into your pond. Upstream, there may be all sorts of fertiliser and pollution coming into the water, and in times of high rainfall it may also bring in silt.  You would also need an abstractio licence.  Tap water and run-off from the garden often contain nutrients in the form of  nitrates and phosphates, which makes your pond more susceptible to algal blooms. Tap water also contains chlorine, although it naturally disappears over a few days. If at all possible, prevent run-off of water into the pond that has passed through fertilised soil.
 
Fish: Fish will eat much of the wildlife in a pond and their excreta will also add nutrients to the pond, increasing the risk of algal blooms. However, with carefully constructed shallows and refuges, it is not impossible for a pond to support both fish and wildlife. For more information see our leaflet To have fish or not? by Ian Thornhill
 
Importing pond life: It is generally advocated not to move either mud or pond creatures from pond to pond, even though it may seem the quick and easy route to introduce wildlife to a pond. Certainly do not move amphibians or their spawn, which can spread red-leg disease and chytrid disease. Unless very isolated, most new ponds will rapidly be colonised of their own accord by blown seeds, or through larvae or eggs carried on pond plants or the feet of birds. There are also legal restrictions for certain invasive species, see Ian Thornhill's leaflet Ponds and the law.
 
Bog gardens and rain gardens: Boggy, saturated ground hosts a range of plants and their associated wildlife even if there is no standing water. Bog gardens can be a good alternative to a pond if water safety is a major consideration. They form naturally where the ground has poor drainage or the water table is high, but can be mimicked by digging out a hole, lining with a pond liner that is spiked with a few drainage holes (you should aim to impede drainage, not stop it altogether), and refilling with the excavated soil.
 
Rain gardens are rather different from bog gardens in that they are low lying areas which have been designed and planted so as to absorb water into the underground strata rather than overwhelm the drainage systems. They are gaining in popularity, and if designed well could become an important element of wildlife gardening.
 
Bird baths: If the only water you have space for is a birdbath, it is still worth adding to your garden. The key principle is to create a 'shallow puddle on a pole'. Birds will often prefer to bathe or drink from a bird bath compared to a pond as it offers a better vantage point from where to keep watch for predators.
 
Temporary ponds: A pond does not have to hold water all year to be of value to wildlife - there can be considerable wildlife value in areas of the garden that are only wet for part of the year (usually the winter and spring). You may have such an area naturally in your garden - if so, consider retaining it 'as is' rather than trying to drain it or turn it into a permanent pond.
 
Safety: Even the shallowest of water can be dangerous for young children. Open, unguarded ponds are a real risk in a garden. Consider either securely fencing off a pond area so that children can't access unsupervised, having a grille fitted over the top, or restricting yourself to a bog garden until the children are older. The shallow water and gently sloping sides to a good wildlife pond should also help should anyone fall in. The Royal Society for the Prevention of Accidents is a good source of information about pond safety.
 
Chemicals in the garden: Fertiliser run-off from the garden to the pond is strongly to be avoided.  Many chemicals used in the garden, including fungicides and insecticides also harm pond organisms.
 
Wildlife access: It is vital that creatures can get into and out of the pond easily, whether they be pond creatures that can't climb well or land creature that might fall in. Gently sloping sides and strategically placed rocks and logs are generally adequate.
 
Water sources: Clean water is an essential component of a healthy wildlife pond. The best water to fill a pond is rainwater. Do not dam or divert any water course to direct water into your pond. Upstream, there may be all sorts of fertiliser and pollution coming into the water, and in times of high rainfall it may also bring in silt.  You may also need an abstraction licence.  Tap water and run-off from the garden often contain nutrients in the form of  nitrates and phosphates, which makes your pond more susceptible to algal blooms. Tap water also contains chlorine, although it naturally disappears over a few days. If at all possible, prevent run-off of water into the pond that has passed through fertilised soil.
 
Above:  This is an interesting pond designed rather cleverly as a combination of an architectural feature and a wildlife pond. It has a stark decking surround and wooden margins on three sides, but shelves pleasingly on the third.
 
This pond could have developed nicely with judicious planting, but is dead and sterile because the designer used anti-rot tanalised timber, which leaks toxins into the water killing plants and animals alike.
 
Until 2006 tanalising mixes used chromium and arsenic as ingredients, although now they has been removed leaving copper and triazole biocides, both designed to kill wood borers and fungi, but toxic to aquatic organisms
 
Nowadays, there are much better options, especially the use of recycled plastic which is inert and doesn't look too bad either.
 
Pond construction and materials
 
There are many websites that will give more detailed instructions on how to create a pond. The key factors to consider are time, money and effort!  Creating a medium-sized pond is a big job, and could cost several hundred pounds to be done well. Skimp, and you may end up with a sub-standard pond that leaks.  For helpful details on positioning, digging and establishing a pond see our leaflet Placing and constructing a garden pond by Ian Thornhill.
 
Other well illustrated website guides on pond construction we recommend:
 
Freshwater Habitats Trust   Written by the top UK pond ecologists
Wild about gardens website  - but we don't recommend adding soil into the pond.
Royal Horticultural Society   Look at pages coming from this link
Froglife's "Just add water"   A substantial but readable guide
British Dragonfly Society     Aimed especially at dragonflies
 
 
Resources available from this page:
Ponds and the law
To have fish or not?
Placing and constructing a garden pond
 
 
Download our How-to guides:
 
How to: Bring water into your garden
How to: Make a pond in a pot
How to: Create and maintain ponds for wildlife