Scarlett Red Hermit Crab

The Scarlet Leg Hermit Crab is a slightly larger relative of the more common red and blue leg hermit crabs. Similar to their close relatives, Scarlet Leg Hermits and powerhouses at consuming nuisance algae including hair algae, diatoms and cyanobacteria. Scarlet Leg hermit crabs make for stunning additions to any reef tank.

Introduction to Scarlet Red Hermit Crab (Paguristes cadenati) – Peaceful & Colorful Cleanup Crew

Scarlet red hermit crabs (Paguristes cadenati) are one of the most peaceful hermit crab species, making them a top choice for reef aquariums. Recognized for their bright red legs and yellow eye stalks, they stand out as both an attractive and functional cleanup crew member. Unlike other hermit crab species, scarlet reds prefer to be housed only with their own kind and should not be mixed with blue leg, red leg, or other colored hermit crabs. They thrive in well-established tanks with ample rockwork, sand, and available empty shells.

Care Requirements

Care Level: Easy – Low-maintenance and beginner-friendly Minimum Tank Size: 10+ gallons Aquarium Setup: Requires rockwork, sand, and spare shells for growth Scarlet red hermit crabs are active foragers, spending most of their time grazing on algae and scavenging for leftover food.

Diet & Nutrition

Scarlet red hermit crabs are omnivorous scavengers, meaning they consume a mix of algae, detritus, and meaty foods. Diet: Omnivorous – Prefers hair algae, detritus, and leftover food Recommended Foods: Hair algae, diatoms, and film algae Uneaten fish food and organic waste Algae wafers and sinking pellets (if food is scarce) Providing supplemental food ensures healthy growth and reduces competition for resources.

Lifespan & Growth Rate

Lifespan: 2-4 years Growth Rate: Slow – Typically reaches up to 1.5 inches As hermit crabs grow, they must molt and find larger shells, so providing a variety of empty shells is essential.

Temperament & Compatibility

Temperament: Peaceful – Less aggressive than other hermit crab species Reef Safe? Yes – Safe for corals and fish Should not be housed with other hermit crab species (blue leg, red leg, electric blue, etc.), as they prefer to be kept with their own kind. To prevent stress, house them only with other scarlet red hermits.

Common Challenges & Considerations

Should Only Be Kept With Their Own Kind: Do not mix with other hermit crab species. May Dislodge Corals: Can accidentally knock over frags or small corals while foraging. Opportunistic Scavenger: If underfed, may pick at soft tissue or weakened tankmates. Providing ample food sources and extra shells ensures a peaceful and effective cleanup crew.

Water Conditions

Temperature: 74-80°F dKH (Alkalinity): 8-12 pH: 8.1-8.4 Specific Gravity: 1.024-1.026