Welcome to the forum!

If you are unsure what chemicals were used in the pond I would take a good representative sample of the material to be dredged out, dry it and send it to be tested, especially for metals like copper.

http://soiltesting.tamu.edu/

www.hoosierpondpros.com


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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).