Astrea Snail

The Astrea Snail (Astraea tecta) is one of the best hair-algae grazers you can add to a reef cleanup crew. Their pyramid-shaped shell hides a hungry herbivore that spends the day mowing film algae, hair algae, and diatoms off rock and glass. Astrea are 100 percent reef safe and pair beautifully with other cleanup crew like our Red Banded Trochus Snails and other saltwater inverts.

Care Guide

• Care level: Beginner. Hardy in stable reef parameters.
• Tank size: 10 gallons or larger. Plan 1 snail per 5 to 10 gallons of established reef rock.
• Water: 72 to 78 F, pH 8.1 to 8.4, specific gravity 1.023 to 1.025, dKH 8 to 12.
• Acclimation: Slow drip acclimate over 60 to 90 minutes. Snails are extremely sensitive to salinity changes.
• Diet: Film algae, hair algae, and diatoms. Supplement with sinking algae wafers or nori only if the tank runs out of natural algae.
• Important: Astrea cannot right themselves if flipped onto their back. Check the tank daily and turn over any upside-down snails.

Specifications

Compatibility

Great with: all reef fish, corals, anemones, peaceful shrimp, and other reef-safe inverts. Excellent partner for Trochus snails (which graze the rocks Astrea can't easily reach).

Caution with: aggressive hermit crabs that may attack the snail for its shell, and predatory wrasses or pufferfish that eat snails. Position powerheads carefully so flipped snails don't end up under intakes.

Recommended Pairings

• Red Banded Trochus Snails for grazers that can right themselves.
• Mexican Red Leg Hermit Crab for substrate cleanup.
• Emerald Crab for bubble algae control.
• Scarlet Skunk Cleaner Shrimp for parasite picking and added activity.
• Browse the full saltwater livestock collection.

FAQ

What's the difference between Astrea and Trochus?
Both are reef-safe algae grazers, but Astrea are smaller, prefer rockwork, and cannot right themselves if flipped. Trochus are larger, more flat-surface focused, and self-right. Most reefs benefit from a mix of both.

How many do I need?
Plan on 1 Astrea per 5 to 10 gallons. Lighter stocking is fine if you already have other algae grazers in the tank.

Will it touch my corals?
No. Astrea snails are strict herbivores and will not damage corals, anemones, or clams.

My snail is upside down, is it dead?
Probably not. Gently flip it back over with tongs. Astrea fall off rocks routinely and need help getting back up. Check the tank once a day and reset any flipped snails.