10 Best Pond Liners 2025 in the United States

The LifeGuard Pond Liner is made from 60-mil thick EPDM rubber, a material known for its durability and flexibility, making it strong enough for heavy-duty uses like supporting large rocks and creating complex pond shapes. Its thickness offers good resistance to punctures and tears. The liner is UV resistant and does not contain plasticizers, so it won’t become brittle or crack over time under sun exposure, ensuring a long-lasting protective barrier for your pond.

It comes with an underlayment that helps protect the liner from damage by sharp objects underneath, though the underlayment is provided in multiple pieces rather than a single sheet. Sized at 30 by 40 feet, it’s large enough for medium to large ponds and shaped as a flexible sheet that can be cut to fit. The liner is certified fish and plant safe, making it suitable for koi ponds, water gardens, and aquaponics without harming aquatic life.

Installation is straightforward since the liner lays flat and is pliable, but the product is heavy (over 500 pounds) and ships via freight truck, which may require careful delivery planning. One downside is that the underlayment’s multiple-piece design might be less convenient than a single-piece mat. This liner is a strong, reliable choice for anyone needing a versatile, fish-safe pond liner with professional-grade durability.

The LifeGuard 20 ft. x 25 ft. 45-mil EPDM pond liner is a solid choice for anyone looking to build or repair a pond or water feature. Made from EPDM rubber, it is both durable and flexible, which helps it withstand outdoor conditions without cracking or becoming brittle like some vinyl liners. Its 45-mil thickness offers good puncture resistance, helping it last longer even with sharp objects or rough surfaces below. The liner is specially designed to be safe for fish, turtles, and plants, making it well suited for koi ponds, aquaponics, or water gardens. It also resists damaging UV rays, which is important if your pond gets plenty of sun.

The large 20-by-25-foot size can cover a wide range of pond shapes, and the material lays flat and adapts easily to curves and shelves, making installation manageable even for DIY enthusiasts. The liner weighs 150 pounds, which may be somewhat heavy to handle alone during installation. EPDM liners generally offer excellent longevity, but if your pond is very large or has unusual dimensions, it is advisable to double-check the fit or consider custom options.

The product comes with a 25-year warranty, reflecting the manufacturer’s confidence and adding peace of mind. For those seeking a reliable, fish-safe, UV-resistant liner capable of handling outdoor ponds and water features well, the LifeGuard EPDM liner is a dependable pick.

The HALF OFF PONDS 50 ft. x 50 ft. 20-Mil LLDPE Pond Liner is a solid choice for pond, lake, or retention basin projects, especially if you need a large, flexible liner that can handle irregular surfaces. Made from LLDPE, it offers good durability with high resistance to punctures and tears, making it reliable for long-term use. Its 20-mil thickness strikes a balance between strength and flexibility, which helps it conform well to gentle curves and smooth transitions but might struggle with very sharp corners or tight bends.

This liner is UV resistant and designed to resist damage from sunlight, with a 10-year warranty when used exposed to sun and an expected life of over 40 years if covered by earth or water, which is great for durability. Importantly, it is safe for fish and plants, so it's suitable for natural ponds and water gardens. The large 50 x 50 feet size is versatile enough for many pond sizes, though it is quite heavy and ships via freight, which means handling and installation might require some effort.

It attaches easily to waterfalls and skimmers but isn’t ideal for complex shapes with tight corners. For those looking for an economical yet strong pond liner that lasts and supports aquatic life, this product fits well, though it may require some care during installation due to its size and flexibility limits.