"Something" is going on at the City Marina, it will soon be sold to developers some of us think and likely be closed and Condominiums be built. I have stayed as we leave permanently next spring and I doubt anything will happen before then.
Anyway that has had a lot of people leave because if and or when that happens, a good Marina will be hard to find, however this results in lots of available space.
It is an old Marina, built I think around the late 50's, however it is right in the old Downtown area of Panama
It does not have floating docks, but there isn't much tide there either.
St Andrews is a newer Marina, in a more touristy part of town and has floating docks.
However the docks are open for anyone to walk around, the old City Marina has locked gates.
You may want to spend some time at Port St. Joe and possibly Carrabelle
Panama City is an old city with a lot of history
Panama City Beach is completely different, very close by, but that is where all the partying by kids
etc. goes on.