If you’re building a large Koi fish pond, then a concrete built pond would be a good option.

　　However, if you’re only building a smaller or more basic fish pond, then a flexible pond liner would be a more effective and also popular choice. The factors to take into consideration are the size of your fish pond and the actual budget as well.

　　In the following article, we’ll take a look at some of the best fish pond liners available on the market and why you should invest in them.

　　Best for Fish: Aquascape PRO Grade EPDM Boxed Liner for Pond

　　When building a fish pond, the underlayment and liner are the foundation of the pond. So if you choose an inferior quality or low- grade pond liner, it will probably lead to a possible leaky pond, costly repairs, and headaches.

　　Aquascape fish pond liners are the industry leaders when it comes to reliability and quality. It is also backed by Aquascape’s industry-leading 20-year guarantee making it the choice of professional contractors and discerning pond builders around the world.

　　Aquascape also sends out certified and pre-qualified contractors that are the best pond builders in the business. These contractors are trained and highly experienced in designing and building beautiful ponds, fountains, and waterfalls. When you deal with Aquascape, you have peace of mind knowing that you are choosing a brand trusted by building professionals and homeowners.

　　Some of the advantages of the Aquascape fish pond liner is its superior elongation and lay-flat characteristics, ease of installation without the need for extra or special tools, as well as exceptional resistance to ozone, solar UV, and oxidation.

　　Pros:

　　●　Superior elongation

　　●　Lay-flat characteristics

　　●　Resistance to oxidation, ozone, and solar UV

　　Cons:

　　●　Prone to leakage

　　Product specifications:

　　●　Dimensions: 10 x 12 feet

　　●　Weight: 1 pound

　　●　Material: 45Mil Epdm Pond Liner

　　Runner up: TotalPond pond skins Pond Liner

　　The TotalPond pond skins Pond Liner is designed by engineers to weigh 30% less than the other 20 mil PVC liners. However, it is still as flexible and strong as these other pond liners. They are also reinforced with a strong polyester weave that is placed between the layers of PVC.

　　The TotalPond pond skins Pond Liner contains a textured surface that leads to positive bacteria growth by providing the right foundation that is also an environmentally friendly one. These PVC liners are also puncture-resistant and UV resistant. This ultimately ensures years of use.

　　Pond liners come in various sizes, and it is recommended that you order a larger size than the hole you are covering since you can always cut off extra pieces. However, if you order a size too small, then it’s basically worthless to you.

　　You can also seam together several pieces of liners to form a large one. Also, be sure to add an extra layer of underlayment before installing the liner. This will keep tears and punctures at bay. Some alternatives for underlayment include old carpets, sand, and any robust sheet of fabric.

　　After allowing the liner to overlap onto the ground, secure it in place with shale, rocks, and other natural material.

　　Pros:

　　●　Lightweight, easy to install

　　●　Reinforced with polyester weave for additional durability

　　●　Textured surface for positive bacteria growth

　　Cons:

　　●　Liner is too thin for use in winter

　　Product specifications:

　　●　Dimensions: 13 x 20 feet

　　●　Weight: 23.3 lbs

　　●　Material: PVC

　　Alternatives: Anjon Lifeguard EPDM Pond Liner

　　Pond liners are the foundation of any water garden, Koi pond, or waterfall feature. LifeGuard pond liners are the best choice for installers and feature owners around the globe. The Underguard underlayment protects and promotes the lifespan of the pond liner, and they both work together to bring unmatched quality to your backyard.

　　These pond liners are marketed in hundreds of pond kits and installed in thousands of water features worldwide. This is due to their reliability and reputation. These pond liners resist UV deterioration and do not contain plasticizers, which may become brittle, leading to splits and cracks.

　　LifeGuard pond liners are virtually indestructible and also unaffected by rot, mildew, hydrocarbons as well as freeze-thaw cycles. The pond liners are also versatile and used in a wide variety of applications such as skimmers and waterfalls, fish hatcheries, retention, and Koi ponds and pond free waterfalls.

　　They are certified fish and wildlife safe by Guardian Systems Inc. and easily attach to skimmers and filtering waterfalls. They can be easily seamed and are compatible with hose and pipe penetration without leaks.

　　LifeGuard pond liners are compatible with a range of water feature projects. It fits into corners and follows the contours along the sides and bottom of your pond. They fit well in ponds with planting shelves.

　　They also fit biological water filters,  shelves identity to biological waterfall filters, skimmers, bottom drains, filter wires, and other filters that require liner attachments. Ultimately, they create a safer and healthier environment for plants, fish, and wildlife.

The results of these claims are available on the manufacturer’s website. The pond liners are also able to withstand extreme temperatures between 170 degrees Fahrenheit to minus 40 degrees Fahrenheit.

　　Pros:

　　●　Durable and puncture-resistant

　　●　Resistant to UV deterioration

　　●　Certified fish and wildlife safe

　　Cons:

　　●　Contains a seam in the middle which makes it prone to future weakness

　　Product specifications:

　　●　Dimensions: 8 x 10 feet

　　●　Weight: 10.88 LBS

　　●　Material: EPMD

　　Best Durability Winner: Firestone EPDM Rubber Pond Liner

　　The Firestone EPMD pond liner and is pre-cut and boxed. There are flexible and creative designs, and the liners are environment and fish friendly. It is one of the easiest pond liners to maintain, and they are designed to last. These pond liners are 15′ x 20′ and approximately 45 inches thick.

　　Pros:

　　●　Pre-cut and boxed

　　●　Flexible designs

　　●　Environment and fish-friendly

　　Cons:

　　●　Product is expensive

　　Product specifications:

　　●　Dimensions: 15 x 20 feet

　　●　Weight: 90 lbs

　　●　Material: EPDM rubber

　　Runner Up: POND BOSS Pond Skins Liner

　　Pond Boss specializes in the latest innovative, and cost-effective water features and gardening products that help you create, enhance, and maintain your own pond, fountain feature, and waterfall.

　　Pond Boss provides you with eco-friendly, and durable equipment such as UV filtration systems, Low water shut off pumps, non-toxic water treatments, pond liners, accessories and so much more.

　　They’ve been bringing high-quality gardening products to the public for over a decade. Their speedy and reliable customer care team is always ready to assist you in creating and maintaining your very own backyard garden feature.

　　Pros:

　　●　Durable

　　●　Safe for fish

　　●　Easy to install

　　Cons:

　　●　Prone to leaking

　　Product specifications:

　　●　Dimensions: 10 x 13 feet

　　●　Weight: 11 lbs

　　●　Material: PVC

　　Pond Liner FAQ

　　What is a pond liner?

　　A pond liner, in essence, is a watertight geomembrane that is used for water retention. Not only is it used in the construction of ponds, but lakes and rivers as well.

　　However, they do need to be protected from sharp objects below the liner and from being ripped or punctured by other objects that are underneath the river or pond.

　　This is why water filters and pumps are available. They keep the want clean and sharp objects away. Protection is offered by layers of concrete, sand, fiber matting, and other materials as well.

　　These pond liners are made in rolls and can therefore be purchased in various different sizes. Just bear in mind that you don’t want to order a pond liner that is too small as it will not fit properly in your pond. Likewise, you don’t want a liner that is too big as it will be a waste of money.

　　So it is recommended that you buy a liner that is slightly bigger than what you actually need. This way, you are safeguarding yourself from going too small, and if it is slightly bigger, you can trim off the excess.

　　What size pond liner do I need?

　　There are a lot of tools available online to calculate the size of the pond liner you need. The calculation is automatic after you enter some required details.

　　Calculating the correct size of pond liner needed is crucial as you don’t want something that is too small as it is not going to fit; likewise, you don’t want a liner that is too big as it will be a waste of money and other pond supplies.

　　So the rule of thumb is that once you’ve found the right size of pond liner, always order a size that is slightly larger than that. This is to ensure that it’s definitely going to fit in your pond and also leave a little room for error.

　　So if it is slightly too big, all you need to do is just simply trim off the excess. Either way, it’s always better to go bigger rather than smaller. A bigger liner will need some adjusting to fit your pond while a small one is of no use to you.

　　How to install a pond liner?

　　Mark out the area that you intend to build your pond using line marking paint, sand or a hose. Prior to digging to the desired depth, decide how many steps or shelves you want in your pond.

　　The steps will make handy exit points should any wildlife fall into the pond. To create a shallow water zone for plants, the first step should be around 20-45 cm deep.

　　There are no hard and fast rules when it comes to how deep a pond should be, so use your discretion. However, you should be aware that the deeper the pond, the easier it will be to maintain.

　　Koi ponds should be approximately 1 to 1.5m deep as these are the requirements. Your local council will make you aware of any regulations governing the depth of ponds, so be sure to check with them.

　　Once the hole has been dug, you can then start to give it some shape. It would help if you also used this time to make sure that there aren’t any roots, rocks or sharp objects on the base or sidewalls.

　　A shovel will ensure that you get the base smooth.

　　In this step, you should focus on what is needed for the pond equipment such as electrical cable trenches and plumbing. You can conceal pump cords and plumbing by capping; however, in many cases, the cable and hose are still visible.

　　If you are not sure of the regulations regarding electrical power cables, consult a certified electrician.

Consider the pond filter in use when considering plumbing. Always seek advice pertaining to pond filters before finishing off the outer areas of your pond to ensure that plumbing has been catered for.

　　In the next step, dig a 15cm wide x 15cm deep trench to create a capillary barrier which will prevent runoff getting into the pond and polluting it with fertilizers and pesticides.

　　It would help if you now chose a high-quality liner. Some of the best liners are reinforced polyethylene and EPDM. Your liner should offer tear resistance, flexibility, and strength. It is also better to order a slightly bigger size than is actually needed than to order a smaller size.

　　Before installing the pond liner, you should put down an underlayment. This extra layer works as padding against sharp objects, rocks and roots. It’s also puncture resistant prolonging the life of your liner and pond.

　　Once this step is fulfilled, you can lay down your pond liner. It should be laid directly on top of the underlayment and should be pulled taut. The liner should rest on the bottom of the pond, walls and shelves.

　　Place smooth rocks around the edges to hold the liner in place as you slowly fill the pond with water.

　　How to find a leak in a pond liner?

　　To check for leaks in the pond liner once it has been installed, you can use the milk squirt method. The liner will need to be inspected once the water level reaches the point where it is no longer dropping.

　　Simply put some milk in a spray bottle and spray it along the edges of the pond. If there are no holes, the milk will cloud the water. But if there is a hole in the liner, the milk will flow towards the hole.

　　How do I fix a pond liner leak?

　　There are a few ways that you can repair a pond liner leak depending on the time frame, and budget that you have. Using a rag, clean around the hole to remove algae and dirt. It is possible to fix the leaky liner without draining the water by using a specific type of sealant. It is, of course, safe for fish and plants.

　　You will need plastic disposable gloves as the sealant is extremely sticky. Once you’ve located the hole in the liner, place the sealant in a caulking gun and squeeze it into and around the hole in the liner. In fact, you should smear it over and around the hole.

　　This will work if it is a tiny hole. If the hole is large, you should cut a small piece of pond liner from the edges and use it to patch the hole. You can place it over the silicon.

　　Conclusion

　　It is always best to do your research before building a pond in your backyard. There is a wide range of options on the market, and it can tend to be overwhelming when the time comes to make a choice.

　　Some of the key points to remember in times like these is that the liner should be flexible, durable and long-lasting. They should also be fish and wildlife-friendly. Also note that irrespective of how strong a pond liner is, it is not indestructible so remove any sharp objects from the pond before laying down the underlayment and pond liner.

　　Your pond liner should also be able to withstand the elements, irrespective of whether it is blazing hot or freezing cold.