I am not aware of any issues thus far using the normal, fine grind crosslink polymer blend, but am aware of 3 failed projects using the course grind. The course grind never wanted to sink, apparently, and as a result blew all over the pond and against the shoreline. While the leaks were not improved, at least the customers were taken care of by the manufacturer.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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