Flexible Versus Preformed Pond Liners – Which One to Choose?

      Comments Off on Flexible Versus Preformed Pond Liners – Which One to Choose?

Pond liners main purpose is to avoid water leakage into the ground, so the issue of getting it refilled frequently is eliminated. Pond liner is not just a sealer but has other crucial functions, which must never be disregarded. Liner acts as a total barrier between soil [at the bottom and pond walls] and water, so the chances of pond water contamination gets eliminated.

Liners also prevent soil erosion, especially at the edges of the pond, during rains. In this way, shape of the pond remains intact and life inside the pond remains undisturbed.

Pond owners prefer two kinds of pond liners – flexible and preformed. Before you decide get to know the benefits and drawbacks of both kinds.

Flexible pond liners

Flexible pond liner is malleable and stretchable, so it is easily adjustable and tweaked to fit the dugout pond without any hassle. Pond owners get to opt from different sizes in simple pre-cut sheet forms. Pond owners need to just line the pond with it.


  • Unlike preformed pond liner, flexible ones can be easily moulded to conform already dugout pond shape.
  • Usually light weight and portable, so you can transport hem easily to pond site.
  • Can be tailored to match pond needs.
  • Flexible pond liner is designed from materials like PVC, LDPE, and Butyl.
  • Materials are good choice as they are inactive or don’t react with water, so aquatic life remains safe in the pond.


  • Butyl and PVC materials for manufacturing flexible pond liners are not easy to find.
  • Therefore cost of liners of these materials are expensive
  • They are prone to getting punctured causing leaks

Preformed pond liners

These are manufactured in a predetermined shape at the factory. Shape is definite, so you cannot make adjustments to preformed pond liner on-site. Several people prefer preformed pond liner because of the following benefits.


  • Once installed will not reveal any fold or pleats round the pond corners because of its definite shape.
  • Flexible ponds bunch on pond corners and installers usually need to fold them properly for neat and lined look, which is not in the case of preformed pond liners.
  • Fiberglass and plastic materials are used to designee preformed pond liner.
  • Fiberglass material is rigid and so when you place it above ground and pour water in it there is no worries about seepage.
  • Plastic preformed pond liners need to be placed right away in the pond, so as to avoid it from breaking.
  • Installation is easy because, you dugout the precise dimension and placing of the liner is required.
  • Plastic preformed pond liners are affordable and easily available in variety of sizes and shapes.


  • Predetermined shape is the major disadvantage.
  • Owners need to dig dimension of same specifications, it means there can be no changes made to design, shape and look, after liner gets installed.
  • Carrying them around for installation becomes hard due to its defined shape and size.
  • Often too shallow, so regulating optimal water temperature for survival of fish swimming inside the pond is hard.
  • Fiberglass preformed pond liner is strong, long-lasting but very large and heavy, so transportation is cumbersome and expensive.

Final decision of pond liner selection depends on pond owners. Make sure to choose a liner you feel meets your unique needs.