When is high tide in Pokemon sapphire?

Remember when you set your clock in your bedroom at the beginning of the game? This is where it comes in handy.

The tides go in and out every 6 hours.

3am-9am: High Tide

9am-3pm: Low Tide

3pm-9pm: High Tide

9pm-3am: Low Tide

The times go by the clock you set in your room.

Good luck.