For the shadow of the tail that will create depth and dimension in your angler fish cartoon, here’s a suitable color choice:

 <Angler Fish Tail Shadow>
1. Deep Aqua - 
                            
                            #005F6B
                         - A dark, muted aqua that provides a subtle shadow effect while aligning with the underwater theme.

This Deep Aqua will help create a natural shadow effect that enhances the tail’s volume without overpowering the cartoon’s bright and playful colors.

Would you like to explore other shadow colors or discuss more design elements, such as textures or backgrounds for the angler fish cartoon?