AllPondSolutions Pond Liner 3 x 2.5m HDPE 300gsm 40yr Warranty
Model: APS-PL300-030X025
Expected back in stock in January
This item is currently sold out
Same day despatch before 3pm *
Free tracked 2–3 days · 1–2 days £4 · Next day £6
Protect your liner with underlay · optional
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About the Pond Liner 3 x 2.5m HDPE 300gsm 40yr Warranty
AllPondSolutions is proud to offer our own branded range of pond liners. This is our heavy-duty HDPE liner at a true 300 grams per square metre, made from 100% virgin polyethylene with a 5% carbon black UV stabiliser.
At 3 x 2.5m, or 7.5 metres squared, this gives a well proportioned garden pond of around 1.5m by 1m at 45cm deep, with room for a marginal shelf along one side. Take it deeper for fish and the pond gets smaller, which is exactly the trade-off the size calculator helps you judge.
Not sure what size you need?
Before you order, it is worth two minutes with our pond liner size calculator. Put in your pond length, width and depth and it will tell you the liner size to buy. A liner that is even slightly short on one side cannot be rescued once the pond is dug, so it is the one thing worth checking twice.
Filtration and volume
A pond this size holds around 450 litres. Every pond with fish in it needs filtration, and the right filter depends on your volume and stocking rather than on the liner. Our pond filter size recommender and pond pump size calculator will work it out from your own measurements, and the instruction leaflet packed with every liner covers the same ground.
Why we quote the weight, not the thickness
Almost every pond liner in the UK is sold on a nominal thickness figure. Weight is the measure you can actually verify. Cut a square exactly 500mm x 500mm from the sheet, put it on kitchen scales, and it will read 75 grams. Nothing else in this category invites that test.
Solid and smooth, not woven
Many liners sold as HDPE are reinforced woven sheet. The weave shows as a grid pattern through clear water and cut edges can fray. Ours is solid extruded film, so you get a clean black finish and nothing for water to track along if the liner is ever pierced.
Working out the size yourself
Take your pond length and add twice the depth, plus 60cm. Do the same for the width. The extra 60cm leaves a 30cm overlap all the way round to anchor the edges. Always round up to the next size, because you can trim a liner but you cannot add to one.
- Liner size: 3 x 2.5m (7.5 metres squared)
- 300 g/m2 solid smooth HDPE, approximately 0.32mm
- 100% virgin high-density polyethylene resin
- 5% carbon black UV stabiliser for long outdoor life
- 50% more material than liners commonly sold as 0.3mm
- Joined with a heat-welded seam, as our maximum extrusion width is 2.1m
- Flexible and straightforward to fit, and easy to trim once in position
- Black finish, supplied folded in its own box
- Free pond building advice sheet with every liner
- 40 year guarantee against UV degradation*
*Guarantee covers UV degradation of the liner material and requires a non-woven underlay to be fitted beneath it. It does not cover punctures, tears or damage caused during installation, by animals or by ground movement. This guarantee is in addition to your statutory rights.
Which liner or underlay do I need?
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Order before 3pm Monday–Friday for same-day despatch. Pallet items: UK mainland 3–5 days FREE, kerbside delivery. Full delivery & returns policy