Star Snail

Star Snail: The Cone-Shaped Algae Grazer

The Star Snail, belonging to the genus Astraea (also frequently classified under Lithopoma), is a cornerstone of the marine aquarium clean-up crew. These snails are instantly recognizable by their conical or pyramid-shaped shell, often featuring ridges or subtle spines that give them a 'star' or 'conehead' appearance, leading to common names like the Spiny Star Astraea Snail, Ninja Star Snail or Conehead Snail. Their shells range in color from pale gray or beige to olive green, sometimes becoming encrusted with coralline algae.

The Star Snail is a voracious herbivore that spends its days (and nights, as it is largely nocturnal) scraping nuisance algae from the glass and live rock. Due to its diet and small size (typically up to 1 inch), it is highly effective at cleaning tight crevices and cleaning around coral bases without knocking over frags.

A major consideration for the hobbyist is that the Star Snail cannot right itself if it falls from the glass or is knocked over onto its back. Regular observation is necessary, and the aquarist must manually turn them over to prevent them from dying.

Diet & Compatibility:

• Diet: This snail is a dedicated Herbivore. Its primary diet consists of diatoms, green film algae, biofilms, and is known to be effective at consuming nuisance hair algae (filamentous algae).
• Feeding: In established aquariums with healthy algae growth, the Star Snail requires little to no supplemental feeding. If algae is scarce, the diet should be supplemented with dried seaweed (Nori) or vegetable-based pellet foods to prevent starvation.
• Reef Compatibility: Yes. This species is completely reef-safe. They are peaceful and pose absolutely no threat to corals, motile invertebrates, or other tank inhabitants. They are a valuable asset in maintaining a clean reef environment.
• Temperament: Peaceful. They are ideal community tank inhabitants. Care must be taken to house them only with peaceful tankmates. Avoid all predatory species, including Pufferfish, Triggerfish, certain Wrasses, and large or predatory hermit crabs (which may try to steal the shell).
• Special Care Note: The single most important husbandry point is that the Star Snail must be checked daily. If found upside-down on the substrate, it must be gently flipped over with a net or tongs, or it will eventually perish.

Quick Facts

• Scientific Name: Astraea spp. (Often sold as Astraea tecta or Astraea phoebia)
• Primary Common Name: Star Snail
• Other Common Names: Astrea Snail, Conehead Snail, Spiny Star Astraea Snail
• Origin: Western Atlantic, Caribbean
• Max Size: 1 – 1.5 inches (2.5 – 3.8 cm)
• Temperament: Peaceful (Sessile Herbivore)
• Diet: Herbivore (Diatoms, Film Algae, Hair Algae)
• Minimum Tank Size: 10 Gallons (for a small cleanup crew)
• Reef Compatibility: Yes (Excellent clean-up crew member)