Help & Advice Frequently Asked Questions Pond FAQs Answers to some Frequently Asked Questions about garden ponds. Jump to... I would like to build a pond, what do I need to know? How big does a pond have to be to attract amphibians? What is the best pond design for amphibians? What kind of pond plants will benefit amphibians and are there any to avoid? I would like to install a pond but I have concerns about safety, what are the alternatives? I'm cleaning my pond/mending a leak, what shall I do with the amphibians I find? I'm filling in my pond, what shall I do with the amphibians I find? How can I make my pond safer for children? When is the best time to carry out work on a pond? The pond water has turned green with algae, is this a problem and, if so, how do I solve it? How can I protect the creatures living in my pond if it freezes? Why shouldn't I introduce fish to my pond? There is a pond on a site that is threatened with development, what can be done to protect it? What does the law say regarding garden ponds? I would like to build a pond, what do I need to know? There are various factors to consider when making a wildlife pond, including depth, shape, location and what plants to choose. The excellent booklet "Creating Garden Ponds for Wildlife" produced in partnership by ARC and our partner Freshwater Habitat Trust gives detailed advice about building garden ponds. The RHS also has a useful guide to wildlife ponds with plant recommendations that can be found here. Back to top How big does a pond have to be to attract amphibians? Any size of pond from a bucket to a swimming pool will be beneficial to wildlife, even if it doesn't attract amphibians. Having said that, even small 'washing-up tub' ponds may provide some benefit to amphibians seeking to keep cool in the summer months. Bog gardens can provide a similar function. Ideally though, garden ponds should be bigger than 2m x 2m to provide an attractive breeding site for frogs, with a section of the pond being at least 60cm deep. This will allow an ice-free area for common frogs to safely lie dormant on the bottom of the pond in winter. There are various factors to consider when making a wildlife pond, including depth, shape, location and what plants to choose. The excellent booklet "Creating Garden Ponds for Wildlife" produced by us and our partner Freshwater Habitat Trust gives detailed advice about building garden ponds Back to top What is the best pond design for amphibians? Frogs, toads and newts can turn up in a variety of ponds, but common frogs and smooth newts will be the most likely visitors to your pond. For any pond design, the most important factor is to have gently sloping sides and plenty of native vegetation so the animals can easily enter and exit the water. A deeper section in the middle on the pond (at least 60cm) will ensure the pond won't completely freeze and any amphibian lying dormant on the bottom of the pond will be safe in icy weather. For more information on pond design, see the excellent booklet "Creating Garden Ponds for Wildlife" produced by us and our partner Freshwater Habitat Trust. The RHS has a useful guide to wildlife ponds with plant recommendations that can be found here. Back to top What kind of pond plants will benefit amphibians and are there any to avoid? A mixture of native emergent, submerged and floating plants is best for amphibians. Marginal plants such as spearwort Ranunculus flammula, water mint Mentha aquatica and yellow flag iris Iris pseudacorus, provide cover as the animals enter/exit the water. Plants such as water forget-me-not Myosotis scorpioides and starwort (Callitriche spp.) will provide egg-laying sites for newts. Submerged plants like curled pondweed Potamogeton crispus and hornwort Ceratophyllum demersum and floating species like white and yellow water lilies (Nymphaea alba and Nuphar lutea) are also worthwhile additions. Ideally choose species that will oxygenate the water. You may need some aquatic soil for the plants (available from garden centres), especially if you put the plants in hessian sacks or planters, which provide more stability and are easier to plant. Don't forget to plant around the edges of the pond, and near by, to encourage invertebrates and to provide shelter for amphibians (particularly metamorphs just leaving the water). DO NOT introduce non-native species as these can be extremely invasive and harmful to the pond, and to other habitats nearby. Plants to avoid include: New Zealand pygmyweed (Crassula helmsii),parrot's-feather (Myriophyllum aquaticum), water fern (Azolla filiculoides), water hyacinth (Eichhornia crassipes) and water primrose (Ludwigia peploides or L. grandiflora). The RHS has a useful guide to wildlife ponds with plant recommendations that can be found here. See their page on invasive or non-native plants and how they damage native wildlife here. Back to top I would like to install a pond but I have concerns about safety, what are the alternatives? Wildlife ponds can be made safe by following the advice outlined in another FAQ in this section: 'How can I make my pond safe for children?' However, if you don't have space for a full-size pond or still have concerns, there are plenty of other options. A mini-pond can be made out of an old tub or sink, which can be left standing in the garden, with pebbles and logs built up around the edge to provide access for wildlife. Make sure there are plants and more pebbles inside so the creatures can get out again. See our Dragons in your Garden leaflet for more information. Alternatively, consider a bog garden. This marshy area may be used by frogs and other wildlife as a place to keep cool, particularly in summer. Back to top I'm cleaning my pond/mending a leak, what shall I do with the spawn/tadpoles/adult amphibians I find? If possible put off the work until late autumn as this is when there are least amphibians in the pond to disturb. If you need to carry out the work urgently during the spring, place the spawn/tadpoles in a tank or bucket of pond water while you do the work and then return them to the pond when you've finished. You might come across adult frogs when doing work on your pond. These should be moved to another area of the garden that provides cover from predators and extreme weather (compost heap, log pile, amongst long vegetation/shrubs). If you're concerned they might keep coming back to the pond and getting in the way of the work, you can hold them in a tank/bucket, as long as it's not for too long, and release them afterwards. There is no organisation that will be able to come and take the spawn, tadpoles or adult amphibians from you. Back to top I'm filling in my pond, what shall I do with the spawn/tadpoles/adult amphibians I find? Amphibian and Reptile Conservation encourages you not to fill in ponds unless there is absolutely no other alternative. If you are filling in the pond because of safety concerns, there are other options you could consider - see our other FAQs relating to making ponds safer for children and concerns about pond safety and pond alternatives. Ponds have enormous value for wildlife in urban areas - allowing populations of amphibians to thrive as well as providing important places for dragonflies and other pond invertebrates to live and breed. Ponds also provide stepping stones for other species to come into urban areas, including birds, bats and even grass snakes. Urban ponds can help buffer the disappearance of natural ponds in the wider countryside - the number of ponds in the UK countryside is estimated to have declines by over a third in the last century. Ponds can be of incredible importance for educating young people. Under supervision, children can see real life examples of many of the things they learn in the classroom, including ecosystems, foodchains, biodiversity and wildlife identification. Plus potential pond-dippers develop a confidence in the wider world, and an appreciation and respect for local nature. Amphibian and Reptile Conservation maintains that other options exist to make ponds safe and often these work out cheaper and actually take less time, money and effort than filling in a pond. If you do chose to fill in your pond, we advise that you wait until autumn when there will be least amphibians in the water to disturb. After filling in a pond please note that you may find amphibians returning to the garden the following spring to breed - see our FAQ 'Why have frogs / toads arrived in spring when there is no pond?'. Be sure to complete all the work in one go - do not leave a drained, empty pond as this can trap amphibians and other wildlife. If you are emptying your pond before autumn, and you have come across frogspawn or tadpoles we would advise that you transfer them to a neighbour's garden pond (preferably within one mile). Do not release spawn or tadpoles into a public water body (reservoirs, lakes/ponds in nature reserves) without permission, and avoid moving water (streams, rivers, canals). Please see the 'Garden ponds and the law' FAQ for more information regarding relocating animals. There is no organisation that will be able to come and take the spawn, tadpoles or adult amphibians off your hands. Back to top How can I make my pond safer for children? Amphibian and Reptile Conservation believes that filling-in ponds should always be a last resort, since the damage this can do to wildlife communities locally can be enormous. Wildlife ponds can be made safe by following the points outlined below: Never leave young children unsupervised near any large container holding water. This includes large plant pots, tub-ponds, paddling pools and garden ponds. Encourage children at every opportunity to respect water. This will benefit many children as they grow and could have wider positive impact. Many more drownings occur in water bodies other than ponds. Put up a fence around the pond. The fence can be made of strong wood, non-climbable grating or with vertical railings no more than 10cm apart; it should be at least 1.1m high. Don't forget to leave a small gap between the ground and fence to allow wildlife access. A childproof, lockable gate is another option. Some people find willow-fencing more aesthetically pleasing. Install a pond grille. A rigid mesh or grille across the pond creates a secure over. The grille needs to be able to support the weight of a child and should remain above the surface of the water at all times. Garden centres stock grates and newer products are easy to install. Gently sloping sides. These are important for wildlife and for people should they fall in and need to get out easily. You could consider these points above as temporary measures while children are smaller. Once children are older you can remove many of these features, promoting the pond as a place for enjoying and learning about the natural world. Back to top When is the best time to carry out work on a pond? If possible wait until late autumn (September/October) to carry out work on a pond as this is when there will be fewest amphibians in it to disturb - froglets will have left and adult frogs won't be returning to lie dormant over winter just yet. Occasionally tadpoles or newt larvae will overwinter in the pond rather than developing and leaving in the summer, so have a good sweep around with a net to check what's in the water before you start work. If you need to undertake work on your pond before autumn make sure you consider the pond's inhabitants - keep them in a tank or bucket out of the way while you work. Back to top The pond water has turned green with algae, is this a problem and, if so, how do I solve it? Green water is caused by algae (microscopic plants) which can cause problems for other pond life by blocking out sunlight and using up vital nutrients. Although some algae is beneficial to the pond (tadpoles feed on it), a sudden algal bloom can be devastating. Algal blooms are more common in new ponds and will often clear naturally once the pond has settled in. In more established ponds the causes can be too much sunlight or an excess of nutrients (e.g. from the use of fertilisers on surrounding land). In the long term, a healthy pond should be able to avoid persistent algal blooms by maintaining the right balance of plants (which will use up available nutrients, block out a little sunlight and provide plenty of oxygen). Another option is to use barley straw or barley straw extract. There is still a lot of debate over how effective this is but it is probably worth a try. Do not treat the water with any chemicals or pond tonics, even those that claim to be wildlife friendly can disrupt the natural balance of the pond and cause more problems than they solve; they may also be only a temporary solution. Back to top How can I protect the creatures living in my pond if it freezes? Frogs may lie dormant at the bottom of ponds in winter. Occasionally, in particularly icy spells, frogs can die of 'winterkill', where toxic gases (released in the pond through natural decomposition of dead leaves) can not escape from the pond due to the layer of ice. Though this can be upsetting to pond owners this phenomenon is largely natural and will only affect a very small percentage of the local frog population. Amphibians can breathe through their skin. Providing that there is sufficient oxygen in the water, they can survive for long periods beneath the ice. A traditional solution has been to create a hole in the ice to allow gas exchange with the air. Recent research suggests that this may be ineffective, and growth of plants and green algae may be more helpful, as these oxygenate the water, even under ice. A hole in the ice probably won't make any difference to the oxygen level in the pond but it may help air breathing creatures which can swim to the surface for air (such as smooth newts). It will also give the birds somewhere to drink. Clearing snow from the surface of a frozen pond may help, allowing more light to enter, hence increasing oxygen production from submerged plants and algae. Never pour hot water on to the ice or use chemicals or salt. Similarly, do not be tempted to smash the ice as this can damage pond liners and plants. The best way to create a hole in the ice is to leave a ball or other floating object in the pond which can be removed to leave a hole after it freezes. Back to top Why shouldn't I introduce fish to my pond? Fish are predators of spawn and tadpoles and even small fish can cause problems by competing with tadpoles for food in the pond. For this reason we advise that you don't introduce fish to your wildlife pond. If you would like to keep fish as well then you will need to create a separate pond. Frogs and toads can also cause problems for fish. During the breeding season male amphibians grab hold of anything that vaguely resembles a female - including fish, other species and other males. Usually the fish is released unharmed but occasionally, if it's held by the gills or for a long period of time, it can die. Back to top There is a pond on a site that is threatened with development, what can be done to protect it? Though local authorities should specify that a survey be undertaken to check for rare species (particularly great crested newts) before a development can take place. It can be beneficial to inform the planning authority if you know of the following species existing in or around the pond: Great crested newt. Natterjack toad (unlikely to be found in habitats other than sand dunes of heathland). Grass snake. Common toad. For information on amphibians and reptiles locally you should contact your nearest Amphibian and Reptile Group (ARG) or your local Biological Records Centre, and if you have records make sure they are submitted to these groups. Back to top What does the law say regarding garden ponds? There are three areas of the law that relate to garden ponds. These are as follows: Moving plants and animals between ponds You should always get permission from any pond-owner should you intend to transfer species between ponds. Movement of some species, if protected or considered damaging to native wildlife, is illegal under the Wildlife and Countryside Act 1981. Transferring fish and some amphibians may also require a licence or consent. Seek advice at every opportunity from the Environment Agency, Natural England, the Natural Resources Wales or NatureScot (Scottish Natural Heritage). Generally, ARC recommends not moving things between ponds unless absolutely necessary as you risk accidentally spreading various invasive plants and diseases. Destroying ponds If you have a pond and are moving house, ask the new occupiers if they plan to remove the pond. If this is the case and you have concerns about this process, or if you're considering filling in your own pond (e.g. due to safety concerns), then ask someone with a garden pond whether they are willing to accept stock. If possible, movements should not be over one mile away. Animals should never be released onto a nature reserve or public place without consent. Release of animals in an unauthorised place could make you liable for prosecution under the Abandonment of Animals Act 1960. If the pond in question contains great crested newts then seek advice from Natural England, the Natural Resources Wales or NatureScot (Scottish Natural Heritage) as this species and its habitats are protected by law (Wildlife and Countryside Act 1981). Non-native animals and plants The release of non-native animals into the wild in the UK is against the law. For pond species this includes the red-eared terrapin and the non-native amphibians. If you come across any of these species, or anything else exotic, please report your sighting soon as possible via the record pool and check our non-native species FAQ. Laws relating to release of non-native plants are more lax, however, we urge the public to be extra vigilant and discourage the purchasing or movement of non-native or hybrid plant species. Back to top Manage Cookie Preferences