Stay away from that 20mil/5yr stuff with our sun/UV problems, If it's for a temp pond ok, but if you start poking around or try to rearrange things after 3-4yrs you better have another liner on hand (and doesn't patch well after 3 yrs.).
20 mil doesn't support larger rocks well either. (tho the 20 mil is so much easier to work with).
Is $40 the total difference between the two costs?
Dr Joe
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