Product details:

Anjon Manufacturing's UnderGuard Nonwoven Geotextile Underlayment adds an extra layer of protection between pond liner and rocky or unstable soilsUnderlayment stabilizes soil and prevents air voids from forming between the liner and earth; reduces wear and abrasion from rocks and roots and extends the life of pond liner. The biggest contributors to Koi pond, water garden, and waterfall failures are poor, unstable soil conditions. UnderGuard Nonwoven Geotextile Underlayment fabrics are perfect for stabilizing soil, preventing rocks and roots from penetrating pond liner, and for creating 'rock pads' to cushion large rocks and boulders placed in the pond on top of the liner. UnderGuard Nonwoven Geotextile Underlayment is EASY to install! Simply lay the pieces next to each other and install the pond liner. Use any extra underlayment to create pads for large rocks and boulders placed inside your pond.