I think it is this:
http://www.pondmegastore.com/shop/product.php?productid=16391
Kelly Duffie may know more about this plant in the open pond.
I've never grown it in a pond so I do not know if it is rampant. It likely does not grow deeper than 3ft.

Last edited by Bill Cody; 08/09/12 09:42 PM.

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