What is the best pond liner material?

EPDM rubber pond liner is widely considered the best choice for most ponds — flexible, UV resistant, fish safe and with a 20-50 year service life. Butyl rubber is similarly durable. PVC liner is most economical for smaller ornamental ponds. HDPE liner is preferred for large commercial and aquaculture applications.

How do I calculate how much pond liner I need?

Liner size formula: Length = pond length + (2 × max depth) + 0.6m overhang. Width = pond width + (2 × max depth) + 0.6m. For a 3m × 2m pond with 1m depth: (3+2+0.6) × (2+2+0.6) = 5.6m × 4.6m liner.

Is EPDM pond liner safe for fish?

Yes, EPDM pond liner manufactured specifically for water features is fish safe — certified to NSF-61 or equivalent for potable water contact. Standard roofing EPDM may contain anti-fungal additives harmful to fish. Always specify fish-safe or fish-pond grade EPDM.

How do I repair a leaking pond liner?

Clean and dry the area around the leak. For EPDM and butyl liners, use a self-adhesive EPDM repair patch cleaned with isopropyl alcohol, overlapping the damage by at least 50mm. For PVC liners, use a PVC repair kit with compatible solvent cement.

What is pond liner underlay?

Pond liner underlay is a non-woven geotextile fabric placed between the excavated pond base and the liner to protect against puncture from sharp stones, roots and ground movement. Use 300-500gsm geotextile underlay — strongly recommended for all installations.