What is the best pond liner for a big pond?

Choosing a pond liner can be a challenge if you don’t know what to look out for. Pond liners come in different types and thicknesses all designed with one primary purpose and that is to hold water. There are many types on the market so in this article we will look at three popular choices available in the UK to help you in the decision process.

Consider the following pond liner features:

  • Tear and puncture resistant to reduce the need for having to repair your pond liner
  • Resistant to UV rays therefore guaranteeing a longer life expectancy
  • High sheet flexibility so that it is easy to push into the corners and contours of your pond build
  • Non-toxic to fish for those wanting to take-up koi or goldfish husbandry

Types of pond liners

The latest trend is to use a flexible pond liner versus a preformed pond. Sheet water containment materials offer design flexibility. It allows you to build a pond to any size, shape or depth. It also offers the means of expanding your pond build or adding a feature such as a stream.

The choice of pond liner tends to be either PVC or a synthetic rubber material. PVC has been around the longest and tended to be the traditional choice. It is the least expensive and it is easy to work with. PVC is a light weight material and conforms readily to the shape of a pond. However, PVC does leach chemicals into the water therefore is not the ideal choice for fish pond builds. It isn’t UV or ozone resistant so needs to be fully covered to avoid environmental damage which would reduce the liners life expectancy. Extreme weather conditions will also affect PVC causing tears and this material can’t be repaired if it punctures.

Rubber liners such as Butyl and EP (Liners Online EP is known as Epalyn) are both very pliable, offer high strength, resistant to UV and adverse weather conditions, non-toxic to fish, easy to repair and likely to last many years (25+ years).

For large ponds we recommend a flexible synthetic rubber pond liner of 1mm thickness. The thickness the durability will ensure it withstands the most demanding conditions.