Related Clues:

• Coral structure
• Bikini feature
• Subsurface hazard
• Titanic problem?
• It's just below the waves
• Keel scraper
• Wreck site
• Big chip off the old block?
• Only about 10% of it is visible
• Helmsman's headache
• Titanic's problem
• Titanic's downfall
• Type of knot
• Coral habitat
• Snorkler's interest