Well now it is morning --- and zero water loss. Which I hope means there is no underground leak.
Today I am going to go take a look at that O-Ring.
To leave my pump / filter running all night - all I needed to do is tell my Electric Company my bank account and routing number and how to access my retirement savings...
OK. Truth is -- I have a timer on it -- I just removed the pin settings so it had no shut off [or start] on it -- the dial just spins and spins.
My water level was "perfect" -- meaning there is a little mark on the skimmer of where the pool should be filled to -- in general -- and that is where I stopped fillng it with the hose yesterday - and where it still is.
So -- just checked the O-Ring and it looked pretty good -- but I wiped it down and lubed it up and primed up that whole area and started the filter again. Will go back in a few and look to see if it looks any different in terms of the water level staying constant and psi.
The pool guys I wanted to come and look just called and have a cancellation today -- but it's $135 just o drop by --- I'd love to avoid that -- but well...