Underlayment

The Underlayment is highly recommended for every pond installation. This soft, non-woven, needle-punched Geo-textile, polyethylene fabric will last 20+ years under your liner.  The Underlayment material spreads easily, and saves time compared to using the old method of newspaper or sand and will aid in protecting the pond liner by adding a barrier between the liner and any unseen rocks or other abrasives that may puncture the pond liner if used alone.  Underlayment will also help with moisture and gases that can accumulate under the liner. Moisture is absorbed into the underlayment and wicked up to evaporate out while gases from organic materials are able to be released.  Underlayment may also be used on top of the liner when placing larger boulders or sharp rocks that may puncture the liner. 

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