I think you'd end up with the plants growing in the shallow layer of soil on top of the liner.

You only need 5-7 ppb of fluridone to control Milfoil. It's sensitive to it, and a little goes a long ways.

How many GC per acre did you stock, and how long have they been in the pond?

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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).