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Pond liner buying guide

Updated: 21 October 2026

You searched for a pool liner on amazon.co.uk and the first results are flat black rectangles priced between about £6 and £26, not the blue vinyl skin you might expect for an above-ground pool. Before you add anything to the basket, you need to know which product family you are in, whether the millimetre or gsm figure on the title is believable, and whether the packet size covers the hole once depth is included. This pond liner buying guide sets that order for the sheets in the [pool liner comparison](/hub/swimming-pools/pool-liner). When you already know you need shaped overlap or beaded vinyl, start on [pond liner vs swimming pool liner](/hub/swimming-pools/pool-liner/sub/pool-liner-vs-swimming-pool-liner) instead of shopping film here.

You searched for a pool liner on amazon.co.uk and the first results are flat black rectangles priced between about £6 and £26, not the blue vinyl skin you might expect for an above-ground pool.

Our top picks

PondKraft PondKraft 4 m x 3 m liner

Best overall

PondKraft PondKraft 4 m x 3 m liner
9.6/10about £22.99
View offer
GARDENIX GARDENIX 2.5 m x 2.5 m 200 gsm

Best value

GARDENIX GARDENIX 2.5 m x 2.5 m 200 gsm
8.8/10about £13.95
View offer
Tezhiie Tezhiie 2 m x 4 m LDPE liner

Alternative

Tezhiie Tezhiie 2 m x 4 m LDPE liner
8.8/10about £25.99
View offer
On this page
  1. 1.Flat sheet or swimming-pool vinyl
  2. 2.Read the thickness before the slogan
  3. 3.Size the sheet to the hole
  4. 4.Underlay is a second product

Flat sheet or swimming-pool vinyl

In the UK trade, a swimming-pool liner is usually shaped vinyl for a known wall height: overlap hung over the coping, beaded into a track, or hooked on a J-hook rail. Dolphin Leisure lists plain blue 16 thou overlap liners from about £233.70 for a 12 ft pool. That is a different object from a 2 m square of polyethylene film at under £10. None of the amazon.co.uk ASINs in this comparison states a bead, a diameter, or a 48 inch or 52 inch wall height. If water sits inside a steel or resin wall with a top rail, stop reading pond-sheet thickness and buy vinyl sized to that pool. If you are digging a hole for a garden pond, you stay with the flat sheets, and thickness still matters. Titles that say swimming pool film, pool foundation, or koi pool are marketing words on a rectangle, not a certificate that the sheet replaces a pool-shop liner.

Read the thickness before the slogan

Specialist pond shops often point lasting garden ponds at rubber around 0.75 mm or 1 mm, or at PVC near 0.5 mm for simpler features. Inside this amazon.co.uk set the stated figures run from 0.1 mm film up to Tezhiie’s 20 mil / 0.5 mm LDPE print, with PondKraft at 0.35 mm and at least 200 g per square metre on a 4 m by 3 m sheet. Three listings print 0.1 mm HDPE: kanghelong at about £5.99 with a single one-star review calling the pack greenhouse film, mawmuaw at about £8.99 with puncture stories from gravel and ducks, and WARM&LOVE at about £6.99 with 500 reviews where thin dominates the text. GARDENIX sells 200 gsm at about £6.72 for 1 m square and about £13.95 for 2.5 m square, without a millimetre figure. Do not read a 0.2 cm dimensions field as thickness. MIKIICOCO’s 3 m by 2 m HDPE sheet has no usable thickness. QWORK prints 0.25 mm but names PVC on the title and HDPE in the bullets. When a listing says heavy duty on 0.1 mm film, treat the millimetre line as the fact. Who should skip the thin films is on best pond liner in this set.
PondKraft PondKraft 4 m x 3 m liner

Testsieger

PondKraft PondKraft 4 m x 3 m liner
9.6/10about £22.99
View offer

Size the sheet to the hole

Council wildlife-pond leaflets and Islington’s pond-building note use the same sum: liner length equals the maximum pond length plus twice the maximum depth, and the same for width, before you add edge overlap. A pond 2 m by 1.2 m with 0.5 m depth needs roughly 3.0 m by 2.2 m of sheet before the bank flap, so a 2 m square from the cheap end of the catalogue is short even if the floor looks similar on paper. GARDENIX’s fitting bullet adds depth to length and width, asks for at least 50 cm overlap, and warns not to cut until the liner is full of water. That is different from the RHS suggestion of about 15 cm to tuck at the edge, and different again from Butek’s note about keeping water at least 0.15 m below the top of the liner to limit wicking. Each figure belongs to its source. Do not merge them into one overlap. PondKraft’s 4 m by 3 m sheet can cover the worked example above. Most 2 m squares cannot.

Underlay is a second product

Geotextile underlay is sold by gsm as fleece, typically 150 gsm on stone-free soil and 250 gsm where rock is likely. That is not the same product as YWKJDDM’s 0.2 mm HDPE sheet, even though Amazon ranks that ASIN under pond liner underlays. World of Water is explicit that sand levels a base but does not replace puncture protection, and that newspaper is not a substitute. Reviews of 0.1 mm film in this set mention holes from gravel, nails, or point loads. Buy underlay, or accept the risk, before you trust stars. PondKraft’s title mentions a 25-year guarantee, but the listing does not include the terms, and specialist guides warn that warranties do not cover stone damage. Stars on WARM&LOVE’s 500-review listing did not stop buyers calling the film very thin. Read family, millimetres or gsm, and size first. Use stars to separate two sheets that already pass those gates. The fitting sequence is on how to fit a pond liner.

Common questions

How thick should a pond liner be for a small UK garden pond?
Shop guidance outside this set often starts near 0.5 mm PVC or moves to 0.75 mm rubber for roots and traffic. Here, PondKraft prints 0.35 mm and Tezhiie prints 0.5 mm. The 0.1 mm sheets are film for light duties, not the default for a stony dug pond.
Is 0.1 mm HDPE a pond liner or a sheet of film?
It is sold as a liner on amazon.co.uk, but UK reviews treat it as very thin plastic. Use it for planters or extra layers. Use a stated thicker sheet, or specialist rubber, if the hole has stones and wildlife traffic.
What is the difference between 200 gsm and 0.35 mm?
Gsm is weight per area. Millimetres describe thickness. GARDENIX’s 200 gsm sheet does not print a mm figure, so you cannot equate it with PondKraft’s 0.35 mm without measuring the delivered sheet yourself.
Do I need underlay as well as the liner?
Yes for a typical garden dig. The thin sheets in this comparison fail in reviews when gravel is left in place. GARDENIX tells you to use underlay. The box is only the sheet.
Is a product titled swimming pool film the same as a swimming pool liner?
No. WARM&LOVE’s title includes swimming pool film on a 0.1 mm flat sheet. A swimming-pool liner is shaped vinyl sized to wall height and attachment type.
Why do the title and the bullets name different plastics?
QWORK is the clearest example: PVC on the title, HDPE in the bullets. Treat that as unresolved listing noise and prefer ASINs where material and thickness agree.
Does a 25-year guarantee replace underlay?
No. The guarantee line on PondKraft’s title is not a substitute for clearing stones and laying geotextile. The terms are not on the listing.
Which decision comes first: size, thickness, or star rating?
Family first, pond sheet versus pool vinyl, then thickness or gsm, then the twice-depth size sum, then underlay, and only then stars within the remaining shortlist.

Related pages

Pool liner for a wildlife pond

Pool liner

Best pond liner: short picks for a prepared pond

How to fit a pond liner: size, underlay, then trim

Pond liner vs pool liner: flat film, not pool vinyl

Sources

Public UK sources used for this comparison. Listing prices, stars and review counts are the amazon.co.uk figures saved for this set on 19 October 2026.

  1. RoSPA pond safety (retrieved 19 October 2026)
  2. RoSPA drowning prevention (retrieved 19 October 2026)
  3. Islington Council pond building guidance (retrieved 19 October 2026)
  4. Newcastle City Council wildlife ponds (retrieved 19 October 2026)
  5. HSE swimming pools (retrieved 19 October 2026)
  6. Consumer Rights Act 2015 (retrieved 19 October 2026)
  7. Dolphin Leisure overlap pool liners (retrieved 19 October 2026)
  8. World of Water pond liner guide (retrieved 19 October 2026)
  9. amazon.co.uk listings for the eleven ASINs (retrieved 19 October 2026)