Related Clues:

• Vitamin K source
• Sushi seaweed
• Green organism
• Seaweed that surrounds sushi
• Oceanic flora
• Unwanted organism in an aquarium
• Source of the food thickener alginate
• Lake plant
• Pool organism
• Water bed?
• Part of many a snail's diet
• Stagnant water problem
• A large brown seaweed
• Gala class of seaweed
• Water plant