mttallery,
If you live in a dry area, it can take months for the soil surrounding your pond to stop wicking. It's usually the top layer, or topsoil that does most of the wicking. If that's the case, the lower the water goes, the more the leak will slow down. If the leak remains fairly constant even after the water level is pretty low, it's a sign you may have a true leak. Sandy topsoil takes longer to soak, as it will wick the water farther from the pond. If you have the sandy stuff, it could take another month or 2 to stop wicking.
Rockeytopper had some great advice. Hedge your bet by being patient, giving the pond time to stop leaking on its own. But have some of that free bentonite handy just in case.
