Hopefully they will pack the clay tight enough so the spring is shut off. There is no one way valve on the spring, so when there is more water pressure in the pond than the spring the water will go out of the pond if it isn't packed tight. The majority of water will get into the pond from surface ground runoff.

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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).