narrowfarm welcome to the PB Forum, that's a neat looking hourglass shaped pond you have.
I can sympathize with you on the problems of a leaky pond, my Dam has leaked starting a year after it was built, but it was done low cost and the soil here is very poor. If it wasn't for the siphon supplying water from a stream I would have no pond.

As far as the DB100, I used it 2 1/2 years ago, it slowed the leak but didn't last, but the leak I had was probably too large for this product to seal.
Here's a link to the disussion on DB100.

http://forums.pondboss.com/ubbthreads.ph...true#Post180064