From the home screen, scroll down to the extended app list, and select Map > > Map Setup > Marine Setup.

Marine Chart Mode

Sets the type of chart the dive computer uses. Nautical displays various map features in different colors so the marine POIs are more readable and so the map reflects the drawing scheme of paper charts. Fishing displays a simplified map presentation for optimal use while fishing.

NOTE: Some features require marine maps (Downloading Marine Maps and Charts).

Appearance

Sets the appearance of marine navigation aids on the map.