Emerald Crab
Facts about the Emerald Crab
The Emerald Crab is also known as a Green Crab, Green Coral Crab or Green Cling Crab. The crab is only about one and a half inches long but it lives in cold temperatures in areas not tolerated by other crabs. They also hold onto rubble well and are not often displaced in high waves and storms. The Emerald Crab is also a popular resident in reef aquariums where they eat gunk other bottom dwellers leave alone.
In the ocean, these little crabs actually live very close together with as many as two dozen Green Crabs is a space no bigger than nine square feet. Their habitat is in rubble zones that have under a foot of water to up to ten feet of water. They live in crevices and rocks on the underside of coral rubble. Marine experts believe that they cling so well because of their rough surface texture. Surge waves which they encounter successfully displace most other ocean life.
If you have a healthy reef aquarium, you should have no problems with keeping an Emerald Crab. They get along with most other tank life and they are herbivorous, which means they will only eat plants and not other treasured animal species. They are great little cleaners and are well liked because they eat bubble algae, which many tank cleaners do not.
If you do not have enough natural food for an Emerald Crab, you might have to supplement its diet with other foods. They will eat dried seaweed, pellet fish food or chopped up meat, such as shrimp. In the wild, they live closely with sea cucumbers, Sally Lightfoot Crabs, Blue Leg Hermits, Astrae ad Cerith Snails, Porcelain Crabs, Surgeon Tangs and Eyelash Blennie.
The Emerald Crab can live with others of the same species but not too many or they will get aggressive with one another. You should only have around one crab for every twenty-five gallons of water in your tank. They usually do well with snails but not always, so if your snails are special to you, be careful with this little green crab until you know for sure they are going to co-exist peacefully.
This crab will also eat coralline algae, which is the purple or red algae that you find on the sides of the tank and in other spots. If you have more than one Emerald Crab, they may go for this algae big-time, so if it’s a favorite of yours, be aware of what might happen. Also, when you first get your Emerald Crab, you need to acclimate it quite slowly to the tank.
Don’t worry if at first your new acquisition hides all the time. Even if you don’t see them you will probably soon start to see the benefits of their clean-up work.