I'm a suspenders and belt type of guy. I'd rather spend a little bit more up front and go a bit overkill rather than have to spend a lot later to repair a dam. Not saying that it'll cause problems if you don't use an anti-seep, just that if it were mine, I'd feel a lot better if I did.

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).