The tidal range on the Pacific side of Panama
has a range of over 15', so marinas
as we know them, do not exist.
In 2001, when I was there, there were two.
Marina Flamenco, on the south side of the breakwater for the entrance to the canal. Note that the canal is on the north side, meaning the south side is exposed to the Pacific swell.
Anador Marina is the mooring
field that used to be the Balboa
Yacht Club. Located just to the West of the entrance to the canal.
Two locks up within the Miraflores Lake next to the Padro Miguel Lock was a funky little marina, Pedro Miguel Boat Club, where I stayed for over three months. I believe it is now closed.
Hope that helps.