Sally Lightfoot Crab [Percnon gibbesi]

Sally Lightfoot Crab [Percnon gibbesi]

The Sally Lightfoot Crab (Percnon gibbesi), also known as the Urchin or Nimble Spray Crab, is a popular, active, and efficient cleaner-up crew member for marine aquariums. They are highly regarded for their ability to consume algae and detritus, particularly Hair Algae. However, they are known to become more aggressive and predatory as they mature, necessitating careful consideration for aquarium tankmates. 

Key Care Information:

Care Level: Easy
Temperament: Generally peaceful when young, but can become semi-aggressive to aggressive as they age

Diet: Omnivore/Scavenger (Algae, detritus, and meaty foods)
Minimum Tank Size: 20–30 gallons, although some recommendations suggest up to 80 gallons to accommodate their need for space

Water Temperature: 72–78°F (22–25°C)

Reef Safe: Yes, with caution. While they do not typically eat corals, they can be a threat to small, slow-moving invertebrates and fish 
Aquarium Setup and Requirements:

Aquascaping: They require plenty of live rock with many crevices, caves, and hiding spots.
Flow: They prefer strong water currents, mimicking their natural habitat.
Substrate: A sandy bottom is suitable, but they primarily inhabit rocky areas.

Lid: A tight-fitting lid is recommended as they are quick and can potentially climb out.
Water Stability: They are sensitive to water parameters and require stable, clean conditions. 

Diet and Feeding:

Primary Food: They graze on green and red algae and detritus.

Supplementation: If algae is scarce, supplement their diet with seaweed (nori), algae pellets, and small, meaty, frozen foods like mysis or brine shrimp.

Frequency: Regular feeding can help prevent them from becoming predatory. 

Tankmates and Aggression:

Suitable Tankmates: Generally safe with corals. Larger, robust fish are best.

Unsuitable Tankmates: Small fish, delicate invertebrates, smaller shrimp, and smaller crabs, as they may be hunted once the Sally Lightfoot is mature.
Compatibility: They can be kept with others of their own species if sufficient food is provided. 

Molting and Health:

They will shed their exoskeleton (molt) once or twice a month, at which point they are vulnerable and need to hide.
Ensure proper calcium, iodine, and magnesium levels in the water for healthy shell development.