Peacock Mantis Shrimp – Decapoda sp.

Overview:
The Peacock Mantis Shrimp (Odontodactylus scyllarus) is a large, burrow-dwelling “smasher” mantis shrimp best kept in a species-only marine setup. Plan for an adult size around 15–18 cm (6–7 in) and provide a secure, escape-proof lid; they are strong, curious, and can push gaps open. A 75–115 L (20–30 gal) tank is a practical minimum, with larger volumes giving more stable water quality. Build a stable burrow using well-set live rock (epoxied if needed) and a PVC cave or rock tunnel, plus 5–10 cm (2–4 in) of sand for digging and comfort. Maintain reef-like parameters: 24–27°C (75–81°F), salinity 1.024–1.026, pH 8.1–8.4, and low nitrate. Strong filtration and good gas exchange matter because they are messy eaters. Avoid thin glass tanks and unsecured heaters; use a heater guard and keep equipment protected from strikes.

Compatibility:
Peacock Mantis Shrimp are not community-safe. They commonly kill or maim fish, crabs, shrimp, and many snails, even if well fed. They are also territorial toward other mantis shrimp. The most reliable approach is keeping one per tank. Some keepers attempt “display-only” tankmates such as fast, midwater fish, but losses are common and the risk is yours to accept. Corals are usually ignored, but the shrimp may rearrange rock and sand, topple frags, and excavate under structures, so secure everything.

Health and Quarantine:
Most problems trace back to water quality, injury, or molting stress. Ammonia and nitrite must always be zero. During pre-molt the shrimp may seal the burrow and refuse food; do not disturb it, and keep parameters stable. Provide a safe, dark retreat to reduce stress. Watch for missing appendages, failed molts, lethargy outside the burrow, or foul odors from uneaten food. Never use copper-based medications in the system. Quarantine and rinse live foods when possible to reduce hitchhikers and pathogens, and prioritize regular water changes to support clean, stable conditions.

This species is a carnivore that naturally preys on hard-shelled animals. Feed a varied mix of marine foods: snails, small crabs, clams/mussels (in shell), shrimp, and quality frozen items like squid, scallop, and marine fish flesh. Include hard-shelled prey regularly to support natural behavior and help prevent overgrown smashing appendages. Adults typically do well with 2–3 feedings per week; juveniles can be fed more often in smaller portions. Offer food near the burrow entrance with tongs, and remove leftovers promptly to prevent nutrient spikes. Avoid freshwater feeder fish and oily freshwater meats; they foul water and can lead to poor nutrition.

Shrimp Snails Crabs
Peacock Mantis Shrimp are highly intelligent, solitary predators that establish and aggressively defend a burrow within rockwork or hard substrate. They spend much of their time modifying their burrow, reinforcing entrances, and surveying their surroundings. When active, they are deliberate and observant, often tracking movement outside their shelter before striking prey. Their powerful smashing appendages are used to break open hard-shelled prey such as snails, crabs, and shrimp, and they will actively hunt rather than scavenge. They are extremely territorial and should never be housed with tank mates, as they will eventually attack and kill other invertebrates or fish. Their behavior is complex and engaging, making them fascinating display animals in species-only systems designed specifically for their strength and intelligence.

FAQ

Frequently Asked Questions

About the Peacock Mantis Shrimp

  • Can a Peacock Mantis Shrimp be kept in a reef aquarium?
    No. Peacock Mantis Shrimp are not reef safe and are best kept in a dedicated species-only system. They are powerful predators with reinforced smashing clubs capable of breaking snail shells, crab carapaces, and even aquarium glass if conditions are poor. In reef tanks, they will systematically eliminate snails, crabs, shrimp, and eventually fish. Even large, fast fish are at risk over time. A Peacock Mantis Shrimp should always be viewed as a display predator rather than a community inhabitant.
  • Can a Peacock Mantis Shrimp really break aquarium glass?
    While rare, it is possible under the right conditions. Peacock Mantis Shrimp strike with extreme force, and thin or stressed glass panels are the most vulnerable. This is why they should be housed in aquariums made of thicker glass or acrylic, ideally with rounded corners and no existing microfractures. Providing a deep sandbed and strong burrow materials such as PVC sections or large rubble reduces the likelihood of the shrimp striking tank walls.
  • Why does my Peacock Mantis Shrimp rearrange rocks and substrate constantly?
    Burrow construction is a core part of their behavior. Peacock Mantis Shrimp are intelligent and methodical builders that create complex tunnel systems used for shelter, molting, and ambush hunting. Rearranging substrate, sealing burrow entrances, and moving rubble is normal behavior and a sign the shrimp feels secure. Tanks should be aquascaped with stability in mind, using heavy rock placed directly on the tank bottom.
  • What should I feed a Peacock Mantis Shrimp to keep it healthy long term?
    A varied, hard-shelled diet is essential. Peacock Mantis Shrimp require crunchy foods to maintain the health of their smashing clubs. Suitable foods include snails, crabs, shrimp with shells, mussels, clams, and occasionally pieces of marine fish. Feeding soft foods only can lead to club degradation over time. Feeding once or twice per week is usually sufficient, as they have slow metabolisms compared to fish.
  • Is it normal for a Peacock Mantis Shrimp to stop eating for long periods?
    Yes, especially before and after molting. Prior to a molt, mantis shrimp may seal themselves inside their burrow and refuse food for several days or even weeks. After molting, they remain hidden while their new exoskeleton hardens. This behavior is normal and should not be interrupted. Stable water conditions and minimal disturbance are critical during this time.
  • Are Peacock Mantis Shrimp aggressive toward humans?
    They are not aggressive without provocation, but they are highly defensive. Never handle a Peacock Mantis Shrimp directly, even outside the water. Their strike can cause serious injury. Tank maintenance should be done carefully, with awareness of the shrimp’s burrow location, and tools should be used instead of bare hands near their territory.

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From the Top Shelf blog, tagged for Peacock Mantis Shrimp.