Emerald Crab (Mithraculus sculptus) | Francois Neo

Emerald Mithrax Crab (Mithraculus sculptus) — Bubble Algae Control & Reef Maintenance

The Emerald  Crab is one of the most trusted natural algae controllers in the reef hobby. Famous for consuming Valonia (bubble algae) and leftover organics, this small green crab is an essential member of any Clean-Up Crew (CUC) focused on long-term balance and low-maintenance reef keeping.

Hand-selected and reef-safe, Emerald Crabs are active grazers that work primarily at night, patrolling rocks and crevices to clean detritus and nuisance algae. They pair perfectly with Blue-Leg Hermits and Snails for complete system maintenance.

Why Choose Emerald Crabs

• Natural control for bubble algae, film algae, and organic buildup.
• Reef-safe when well-fed; peaceful and beneficial in mixed reefs.
• Excellent scavengers — clean up leftover food and detritus.
• Active mostly at night, providing continuous cleaning.
• Compatible with most snails, hermits, and small fish.

Pack Options Available

• 2-Pack: Ideal starter set for nano or small reefs (up to 20 gallons)
• 5-Pack: Great for 20–50 gallon mixed reefs
• 10-Pack: Perfect for 75–100 gallon or multi-tank systems

François’ Rule: One Emerald Crab per 15–20 gallons ensures natural algae control without overstocking.

Behavior & Care

• Nocturnal and shy — often hide during the day and clean at night.
• Feed occasionally with seaweed, pellets, or meaty foods if algae is scarce.
• Provide stable rock structures to explore and graze on.
• Always drip acclimate slowly before introducing to your aquarium.
• Avoid housing multiple large males in very small systems.

Shipping & Guarantee

• Shipped in temperature-controlled packaging (Mon–Wed)
• Live Arrival Support included
• Responsibly collected and fully reef-safe

Perfect Companions

• Blue-Leg Hermit Crabs — active grazers for rock and sand
• Astraea Snails — glass and surface cleaners
• Trochus Snails — rock and overflow cleaners
• Nassarius Snails — detritus and sand cleaners

From reefers, for reefers — The François Neo Way.

Tags: emerald crab, mithraculus sculptus, reef clean up crew, bubble algae control, reef tank maintenance, aquarium partners, François Neo, reef kit, nano reef, AIO reef.