I think in your situation I'd try hydrated lime. Ewest or others can give you an idea how much to use. After you're done, you've prelimed the pond for the refill.

Hopefully the amount required for 1 acre, max depth 8 feet, er, inches, is not prohibitive.

Last edited by Theo Gallus; 10/01/07 01:35 PM. Reason: I can't tell inches from feet
"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
[Linked Image from i.pinimg.com]