waterfall/leaking "upper" pond
I have constructed a two level pond and for the life of me, cannot get the waterfall to work without losing water. I have concluded that the level of my waterfall is probably too high and the upper pond cannot move the water to the lower pond fast enough, causing to overfill and leak water out a low spot on the edge of the liner.
Before I attack the problem by removing the mortared stone that makes up the waterfall, are there any suggestions as to how I can fix this problem?
fyi both the upper and lower ponds were constructed with EPDM, and stone was mortared to cover the liner at the water line and keep unwanted rain runoff out of the pond. I mortared the entire thing, so in order to get the pond not to lose water, I am going to have to "undo" the waterfall and either/or make it lower, so the upper pond wont overfill and leak and / or make the waterfall wider to allow the water to leave the upper pond quicker.
I hate to think of having to remove the mortared waterfall but can think of no other option.