Application

Box welded liners for koi ponds

Koi ponds demand precision. A box-welded liner fits perfectly from day one — no creases, no trapped corners, no excess material. Just a clean, professional finish.

Why choose a box welded liner for your koi pond?

Zero creases at the corners

Koi are sensitive to sharp folds where sediment collects and bacteria thrive. A box-welded liner has no folded corners — just clean, welded joints.

Exact fit for any depth

Koi ponds are often 1.2–1.8m deep. We manufacture to any depth — and the liner fits without any excess material to trim or fold.

Drawing approval before manufacture

Every liner starts with a technical drawing you sign off. No koi pond liner is made until you have confirmed the dimensions are correct.

Shapes we manufacture

SquareClean lines, equal sides — ideal for formal koi ponds
RectangleThe most common koi pond shape — any aspect ratio
CircleRound koi ponds up to any diameter
L-ShapeSplit-level or extended L-shaped ponds
With StepsMulti-level ponds with integrated planting shelves
BespokeIrregular shapes — call us to discuss

What to measure

For a koi pond, you need four measurements:

  • Length (m) — internal measurement at the longest point
  • Width (m) — internal measurement at the widest point
  • Depth (m) — from the top of the liner to the base
  • Lip allowance (m) — how far the liner should extend over the coping

Not sure what to measure? See our measuring guide.

Project photography placeholder

Frequently asked questions

We recommend our 1.0mm heavy-duty grade for koi ponds. It offers additional resistance to puncture and abrasion from the koi themselves, and gives extra durability at the weld points.

Yes — if your pond design includes a bottom drain, we can pre-cut and weld a fitting patch into the liner. Please mention this when you request your quote.

There is no upper limit on depth. We have manufactured liners for ponds in excess of 2.5m deep. Just provide us with your exact depth measurement.

Yes. Our range of pond liners are inert once installed and safe for fish and aquatic life. It contains no plasticisers or additives that leach into the water.

Ready to get a quote?

Send us your dimensions — we'll reply with a price and a technical drawing the same working day.

Get a free quote →
Chat with us