I may have misunderstood the original post,, was this pond full in Feb of 2021 or was it a yr ago, 2020? that would make a huge difference in gpm of water exiting the pond.
Secondly if you are way down to 25% capacity and still losing inches per day you may have come close to a gravel seam below your pond that may be draining your pond out and surfacing some distance behind the pond if surfacing at all, which is an even bigger problem then lack of compaction, that would show lack of coring under the dam. Good Luck! keep us posted.
Was finished building Jan 2021, Full Feb 2021, and currently down to 25% full.
