I need some advice on how to separate stones and liner that have been black foamed together. I've had a significant water loss problem that I isolated to one stream. The loss is most pronounced when there is a turbulent flow of water in the stream and less pronounced with a reduced flow.

Figuring I had water loss through the rocks, in folds and over the liner, I took the stream sides and banks apart and did a major (or so I thought) foaming with black waterfall foam. You guessed it--there is still a water loss and I am literally stuck with lots of black foam in the rocks.

In order to try again, I need to move rocks while dealing with the dry foam. My real concern is pulling rocks away from the liner where there is foam connecting the two surfaces. I don't want to tear the liner or puncture it with any tools. There just hasn't been time for me to explore or to start, so maybe I am too concerned?

Before I do start, can anyone give me suggestions on separating foamed-together stones and liner?

Thanks in advance - Mike