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Emerald Crab (Build Your Own Kit)
Please Note: Due to variations within species, your item may not look identical to the image provided. Approximate size range may also vary between individual specimen.
Emerald Crab (Build Your Own Kit) (Mithraculus sculptus)

Quick Stats

Care Level Easy
Temperament Semi-aggressive
Color Form Green
Diet Omnivore
Reef Compatible Yes
Water Conditions 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.023-1.025
Max. Size 2½"
Origin Caribbean
Family Majidae
Supplements Calcium, Magnesium, Iodine, Trace Elements
Compatibility View Chart
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The Emerald Crab, also known as the Emerald Mithrax Crab or Emerald Mythrax Crab, is a hardy and beneficial crustacean with an attractive shiny green coloration. It is easily identified by its flat compact body, textured pebbly carapace, and a set of spiky, walking legs covered in bristly hairs.

This ornamental crab is popular among marine aquarium hobbyists of all skill levels and utilized for its gregarious scavenging abilities. The Emerald Crab is an opportunistic and enthusiastic feeder with a hearty appetite for a wide variety of items including uneaten meaty foods as well as many types of nuisance algae. The Emerald Crab makes an invaluable addition to your natural reef-cleaning arsenal as it will eat bubble algae, often deemed unpalatable by many other algae eaters.

Native to the reefs of the Caribbean, the Emerald Crab is nocturnal and hides in caves and amongst rubble during the day. In the home aquarium, the Emerald Crab requires a well-established aquarium with plenty of rockwork and hiding places. Once familiar with its surroundings, the Emerald Crab will venture out of hiding during the day to forage on algae.

Pay particular attention to ensure an ample supply of food for the Emerald Crab. Otherwise, this tenacious scavenger may turn to corals, invertebrates, or small fish for a food source. However, when well fed, most Emerald Crabs are very tolerant of their tankmates and highly compatible in reef environments. If there is insufficient algae, supplement the diet of the Emerald Crab with dried seaweed and chopped meaty foods, such as shrimp, as well as a quality pellet fish food.

Like other invertebrates, the Emerald Crab does not tolerate copper-based medications or fluctuating water parameters.

Approximate Purchase Size:  1/2" to 1-1/2"

PLEASE NOTE: Prices listed include shipping & handling if your order totals $75 or more.
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Customer Testimonials

David C. Long Branch , NJ
This crab is great, very cool looking and peaceful. He also does not mess with my corals as of yet. Seems to pick and eat alot of algae and waste. Shed his shell whole which made my g/f think he was a goner. Bright green with white tips and fuzzy legs. Makes a good addition to pop out from time to time.
Marc D Hillsborough , NJ
This guy is great. I put him in the tank and he was so anxious to start eating, he ate some of the sand.
Vince D Ashbburn , VA
Received two of these little guys today are they are already doing their job cleaning rock. It is really amazing to watch them as they scour for food. Great addition to my tank!!
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