From what I've heard, none have ever been punctured by a hook but then I wouldn't want to find out so that section of pond will be off limits as a precautionary measure. I cannot wait to get this geo in, my LP bills are out-of-sight $2.42 a unit and last one was $613.40 for a half fill. It's only going to get worse year-after-year. I figure this one will pay for itself in 5 years.