Horseshoe Crab – Limulus polyphemus – Small

The Horseshoe Crab has a body shape much like a horseshoe. Their hard body shell makes them almost impervious from above but if flipped over onto their backs they will become defenseless and can become food for any number of animals. They are excellent for burrowing into the substrate and will agitate the gravel in search of food and detritus.

At a small size they are fine in most aquariums. However, as they mature and grow to a size on average of 8-1 inches wide, they will become destructive and may harm small fish and invertebrates that get in their way. These larger horseshoe crabs will only be able to be housed in larger aquariums of 250 gallons and larger.

It is a good idea to feed your horseshoe crab frozen food such as shrimp, clam, squid, and many other types of meaty foods at least once a week if there will not be enough to feed them in the aquarium’s substrate.