Bentonite for Ponds | Bentonite Pond Sealer
Bentonite for Ponds. To properly apply bentonite as a pond seal, the pond must be drained and the bentonite clay then incorporated into the soil of the pond bottom and sides.. The application rate for bentonite ranges from 2 pounds to more than 6 pounds per square foot depending on the soil characteristics. For clay soils, 2 pounds per square foot may be sufficient.