Not every night but a few times a week about 1-2 hours after lights out there is a loud sound that almost sounds like a rock falling in my sump .
but there are no rocks in the sump to fall
the only thing in my sump that I know of is cheato , a few mesh bags of media . And skimmer pump .
but there are no rocks in the sump to fall
the only thing in my sump that I know of is cheato , a few mesh bags of media . And skimmer pump .
They're 95% blind.

