I accidently posted this in the arrow crab thread!
Sally Lightfoot Crabs are usually very energetic, and can be entertaining to watch. They are not considered to be particularly aggressive, and can do well in a variety of community tanks. Sally Lightfoot Crabs are particularly useful as cleaners, eating algae and other debris that they find in their aquarium. They are often found scavenging in live rock. When large enough, Sally Lightfoot Crabs may eat smaller fish that have died. Sally Lightfoot Crabs are generally considered to be reef safe, although many will walk indiscriminately over corals, causing them to close or retract. This condition is only temporary and usually causes no damage to the coral. The Sally Lightfoot Crab generally gets along well with other Sally Lightfoot Crabs. However, more aggressive crabs, or other, larger species, may eat Sally Lightfoot Crabs. On the whole, Sally Lightfoot Crabs are quite hardy and rather easy to care for. However, they cannot tolerate poor water quality, and may have molting problems if levels of trace elements or minerals become depleted. Hiding places, particularly open rockwork, will be utilized if provided. In the wild, Sally Lightfoot Crabs are often found hiding in rock crevices or under sea urchins.
The Sally Lightfoot Crab grows to lengths between 3 and 5 inches (8 and 12 centimeters). They are rather flat and low to the ground and have been called "spider-like" or quadratic in shape. These crabs are greenish brown in color. Their legs are marked with yellow or orange bands, particularly about the joints. Sally Lightfoot Crabs have two antennae, which are almost constantly in motion.
A single Sally Lightfoot Crab can be kept in a 25 gallon aquarium. Some people offer these crabs an amphibious set up, with a rock or substrate area that is not submerged. If this type of setup is provided, take care that the crab cannot crawl out of the aquarium. Sally Lightfoot Crabs normally do well in temperatures between 72 and 78 degrees Celsius (23 to 26 degrees Celsius). The pH value should be 8.3 to 8.4 and the specific gravity should have a value between 1.023 and 1.025. Many people prefer to add iodine supplements to tanks where Sally Lightfoot Crabs are kept to ensure that the crabs do not have problems in a molt. Generally, a substrate that would allow this crab to burrow should be utilized. Multiple Sally Lightfoot Crabs may be kept in the same aquarium; however, you should not crowd them. One crab for every 25 to 50 gallons of water is generally considered appropriate. Because they are rather small and rather non-aggressive, Sally Lightfoot Crabs might be eaten by larger or more aggressive animals such as trigger fish. Hiding places should be provided. Sally Lightfoot Crabs will normally eat detritus found in an aquarium and can be quite useful in this capacity. Because they are opportunistic scavengers, Sally Lightfoot Crabs may also eat fish that have died, if they are of appropriate size. Some people believe that large Sally Lightfoot Crabs may even go after small fish species, even if the fish are healthy, so care should be taken when keeping this crab with small juveniles or small species. Supplemental feeding of dried seaweed or small meaty items will generally be necessary in tanks with low levels of algal growth.
