Emerald Crab

Emerald Crab

Mithraculus sculptus

Also known as: Emerald Mithrax Crab

🧂 Saltwater ✌️ Peaceful 🟢 Easy 🌿 Herbivore Reef Safe (Caution)

Bright green crab that eats bubble algae (Valonia) which few other organisms will touch. Useful cleanup crew member.

Tank Size

10 gal
minimum (20+ preferred)

Temperature

74–82°F
23–28°C

pH Range

8–8.4
water acidity

Max Size

2"
5.1 cm

Lifespan

2–4 years
typical in captivity

Swim Level

Bottom
preferred zone

Care Notes

Generally reef-safe but large, hungry specimens may pick at corals if underfed. Best algae control for bubble algae.

Feeding

Bubble algae, hair algae, and nori. Supplement with meaty foods if algae is scarce.

Compatible Tank Mates

Blue Green Chromis 3" Pink Skunk Clownfish 3.5" Skunk Clownfish 4" Orange Skunk Clownfish 4.5" Talbot's Damselfish 2.5" Lubbock's Fairy Wrasse 3" Melanurus Wrasse 5" Cleaner Wrasse 4" Yellow Coris Wrasse 5" Carpenter's Flasher Wrasse 3" Firefish Goby 3" Yellow Watchman Goby 4"

Use Caution With

Ocellaris Clownfish 3" True Percula Clownfish 3" Yellowtail Damselfish 2.5" Yellow Tang 8" Kole Tang 7" Clarkii Clownfish 5" Tomato Clownfish 5" Scopas Tang 8" Convict Tang 8" Azure Damselfish 2.5" Springer's Damselfish 2" Cinnamon Clownfish 5"

Incompatible With

Maroon Clownfish 6" Blue Devil Damselfish 3" Blue Tang 12" Powder Blue Tang 9" Naso Tang 18" Achilles Tang 10" Purple Tang 10" Three Stripe Damselfish 3" Domino Damselfish 5" Four Stripe Damselfish 3" Jewel Damselfish 6" Blonde Naso Tang 16"

Check Compatibility

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