Geotextile fabric, thicker is better. I'd be concerned about a 3' wide shelf with 2' or 3' dia rocks on it collapsing over time and the rocks rolling into the pond. Just a SWAG here, but I'd feel better with a 6' wide shelf with 2'-3' dia rocks.


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).