Pond Liners

Pond liners for backyard ponds, koi ponds, and water features

A pond liner is the single most important component of any pond build. Without a quality liner, water seeps into the surrounding soil, eroding the banks and draining the pond over time. The right pond liner holds water reliably for decades — protecting your fish, your plants, and your investment in the pond itself.

We carry EPDM rubber and PVC pond liners in a wide range of sizes, from small water garden cuts starting around $200 up to large custom dimensions for multi-acre projects. All of our liners are fish-safe and UV-resistant, and our Anjon LifeGuard EPDM liner carries a lifetime warranty when installed with UnderGuard underlayment — the best warranty available in the industry.

Types of pond liners — which one is right for you?

45 mil EPDM rubber pond liner EPDM is the material of choice for most pond builders, and for good reason. It's flexible enough to conform to any shape — irregular edges, waterfalls, bog areas — and it stays pliable in temperatures from -40°F to 175°F without cracking or splitting. EPDM contains no plasticizers, which means it won't become brittle over time the way PVC eventually can. Our Anjon LifeGuard 45 mil EPDM liner is certified fish and wildlife safe and carries a lifetime warranty when installed with UnderGuard underlayment, or a 25-year warranty without it. If you're building a pond that's meant to last, this is the liner to choose.

60 mil EPDM rubber pond liner For larger or deeper ponds, commercial applications, or any situation where extra puncture resistance matters, the 60 mil EPDM is the step up. Same flexibility and fish-safe certification as the 45 mil, with additional thickness for demanding environments.

20 mil PVC pond liner PVC is lightweight, affordable, and easy to work with — especially for first-time pond builders and smaller water features. It's more budget-friendly than EPDM and adapts well to tight angles and precise contours where a thicker liner might be harder to manage. Backed by a 5-year manufacturer warranty. A practical choice for garden ponds, water gardens, and features where budget matters more than long-term durability.

Koi pond liners Koi ponds have specific requirements — deeper water, higher water volume, and fish that are more sensitive to water chemistry than most species. Our koi pond liner options are selected for extra durability and fish-safe materials. If you're building a koi pond from the ground up, see our koi pond kits for a complete solution.

UnderGuard geotextile underlayment Not technically a liner, but just as important. Underlayment goes between your liner and the soil, protecting the liner from rocks, roots, and sharp objects that cause punctures from below. It's required to qualify for the Anjon LifeGuard lifetime warranty, and we recommend it regardless — the cost of underlayment is far less than the cost of a prematurely damaged liner. Order underlayment to match your liner dimensions.

How to size your pond liner

The formula is straightforward. Add twice the depth plus two feet of overlap to both your length and width:

• Liner length = pond length + (2 × depth) + 2 ft
• Liner width = pond width + (2 × depth) + 2 ft

Example: A pond that is 12 ft long, 8 ft wide, and 3 ft deep needs a liner that is at least 20 ft × 16 ft.

For round ponds, use the diameter as both your length and width in the formula. For irregular ponds, use your longest measurement and your widest measurement.

Not sure what size you need? Call us at 888-825-6214 and we'll help you calculate the right dimensions before you order.

Does my pond liner have a leak? Start here before replacing it

Not every leaking pond needs a new liner. Small holes and seam failures in EPDM liners can often be repaired quickly and inexpensively:

• DuraLiner Pond Patch Kit ($38.43) — Fixes small holes in any EPDM rubber liner. Includes two 6"×6" patches, primer, a seam roller, scrubber pad, and gloves. If your liner has a pinhole or small tear, this is the right starting point.
• DuraLiner Edge Sealant ($20.49) — An 11oz tube that seals liner edges and seams. One tube covers approximately 20 lineal feet at 1/4" bead coverage. Use this when water is escaping between liner panels or around edges rather than through a hole in the liner itself.

If you're not sure whether you need a repair or a full replacement, call us at 888-825-6214. We can help you figure out what's actually happening before you spend money on a liner you might not need.

Frequently Asked Questions About Pond Liners

What thickness of pond liner do I need? For most backyard ponds and koi ponds, a 45 mil EPDM liner is the right choice — it's thick enough to resist punctures, flexible enough for any shape, and backed by the best warranty in the category. For larger commercial ponds or situations where extra puncture resistance is needed, the 60 mil EPDM provides additional protection. PVC at 20 mil is suitable for smaller water features and garden ponds where budget is the primary consideration. When in doubt, go with 45 mil EPDM — it's the most widely used thickness for a reason.

How long do pond liners last? A quality EPDM liner installed correctly with an underlayment can last the lifetime of the pond. Our Anjon LifeGuard liner is warranted for life when installed with UnderGuard underlayment, and 25 years without it. PVC liners typically last 10 to 20 years depending on UV exposure and conditions. The biggest factor in liner longevity isn't the material — it's installation. Sharp objects beneath the liner, improper anchoring, and UV exposure at the edges are the most common causes of early failure.

Do I need an underlayment for my pond liner? Yes — always. Underlayment protects the liner from punctures caused by rocks, roots, and other sharp material beneath the surface. Even in seemingly clean soil, small stones shift over time and can create pressure points that eventually wear through a liner. The cost of underlayment is small relative to the cost of a liner replacement. And if you're installing an Anjon LifeGuard EPDM liner, underlayment is required to qualify for the lifetime warranty.

Can I use a regular tarp instead of a pond liner? No. Tarps are not designed for permanent water retention — they degrade quickly under UV exposure and water pressure, and they're not fish-safe. A pond liner is specifically engineered to hold water long-term without degrading or leaching chemicals harmful to fish and plants. The difference in cost between a tarp and an entry-level PVC liner is not significant enough to justify the risk.

How do I calculate how much pond liner I need? Use this formula: add twice the depth plus two feet to both your pond length and width. A 12 ft × 8 ft × 3 ft deep pond needs a liner of at least 20 ft × 16 ft. Always order slightly larger than your minimum — you can trim excess, but you can't add material once the liner is in. For large or irregular ponds, call us at 888-825-6214 and we'll help you calculate the right size.

How do I install a pond liner? Start by excavating to your desired depth and removing any sharp rocks or roots from the soil surface. Lay your underlayment first, smoothing it against the contours of the excavation. Then drape the liner over the hole, working from the center outward to remove folds. Secure the edges by burying them in an anchor trench around the perimeter, leaving a few inches of liner visible above the waterline. Fill the pond slowly — the weight of the water will press the liner into the contours naturally. Trim any excess liner once the pond is full. If you run into questions during installation, call us at 888-825-6214.

What's the difference between EPDM and PVC pond liners? EPDM is a rubber material — flexible, durable, and rated for extreme temperatures without becoming brittle. It's the professional's choice for most pond applications and carries significantly longer warranties. PVC is a plastic material — lighter, less expensive, and easier to work with for beginners, but less durable over the long term. For a pond you plan to keep for many years, EPDM is the better investment. For a small water feature or a first pond where budget matters, PVC is a reasonable choice.

Do you carry pond liner repair products? Yes. We carry the DuraLiner Pond Patch Kit ($38.43) for fixing small holes in EPDM liners, and the DuraLiner Edge Sealant ($20.49) for sealing liner edges and seams. Both work with any EPDM rubber liner. If you're not sure whether you need a repair or a full replacement, call us and we'll help you figure it out.

Whether you're building a new pond from scratch or replacing a failing liner on an existing one, we're here to help you get it right. Browse our liner options above, use the size formula to calculate your dimensions, and call us at 888-825-6214 if you have any questions. We also carry complete pond kits if you're starting from scratch and want everything in one order.