The tide database that gets installed by OpenCPN by default includes tides for only part of the world:
- USA & Canada
- Europe
- Australia & New Zealand
- Japan

This file can be added to OpenCPN Tide Definitions to add tide stations for the rest of the world.

For greater details:
https://opencpn.org/wiki/dokuwiki/doku.php?id=opencpn:manual_basic:set_options:charts:tides-currents#using_alternative_data_sets

(Or google "OpenCPN.org Tide")

To Install
- Unzip the folder somewhere (Documents folder recommended)
- In OpenCPN -> Settings / Charts / Tides & Currents
- Add Dataset
- Browse to where you've unzipped this folder
- Select the tide IDX file. (in this case HARMONIC-World.IDX)
- Make sure Show Tide Stations is checked in chart settings (lower right hamburger menu)
- Observe that you now have tide stations all over the world (green icons)