Gardening article By Bunny Guinness, The Telegraph.
"If you are starting a new pool or pond, the choice of liner is very important. Butyl has been superseded; EPDM rubber is far better. It is not degraded by UV light and has a 25-year guarantee. Make sure it is 1mm thick. I always specify a blanket underlay (NP 300) below and usually above the liner too. If labradors, children and deer are going to stray in, it protects the liner."
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