Related Clues:

• Large brown seaweed
• Sea lettuce, for one
• Morsel for a sea snail
• Snack for a surgeonfish
• Aquarium dweller
• Pond organism
• Green growth
• Aquatic organism
• Aquarium problem
• Pond plant
• Seaweed, for one
• Pond life
• Pond growth
• Primitive water plant
• Bit of seafloor flora