Humminbird HELIX 9 Operation Manual page 59

Change the View Colors
The DI Colors menu changes the palette used to display sonar returns on the view.
Change the Down Imaging Colors Palette
1. Down Imaging X-Press Menu: With a Down Imaging View displayed on-screen, press the MENU key once.
2. Select DI Colors.
3. Select a palette.
Down Imaging View with Palette 10 Selected (DI Colors)
59 Down Imaging Sonar