There is not much literature regarding the care and husbandry of many of the small land crab species such as the Rainbow Land Crab or the Vampire Crabs, so this guide is to give some basic care advise.
Most of the crab species live in tropical environments on the sandy banks of rivers and lakes. They are semi-aquatic, but do very well living in humid well planted environments with access to fresh or brackish water. They do enjoy still water without too much of a flow and require hiding spots such as dense planting or rock hides.
Most crabs will live 2-3 years in good conditions.
We would recommend giving the larger rainbow crabs 25-30cm floor space per crab, however the smaller vampire crabs 10-15cm space per crab. A radio of 80% land to 20% water is a good combination with a substate of 3-4 inches. This will allow the crabs to burrow should they want.
A mix of sand, sandy soil and moss will help keep the humidity as well as allow the crabs to burrow and hide.
Most of the crabs prefer a humidity of around 65-75% humidity
Land crabs are generally omnivorous. This means they will eat both plant material and meat. In the wild the species would feed on dead insects, ripe fruits and anything else washed up. They really aren't that fussy.
Most crabs will enjoy fresh or frozen shrimp, bloodworm, crickets and even worms. As well as his they will take a range of fish flakes and pellets and algae wafers.
Calcium is also really important to your crabs. Green veg such as spinach and broccoli as well as cuttlefish bone will help them to continue to grow well.
GROUP LIVING & BREEDING
Most crab species will live happily together if plenty of space is provided. Vampire crabs particularly are quite docile therefore will happily live together as well as sharing their waterways with fish and other small species.
Aggression may occur during breeding season only.
Most crabs live in quite exposed river banks so will be exposed to strong UV. It is important to provide the crabs with good lighting but with plenty of good hiding spots to get away form the light. We would recommend an Arcadia jungle dawn. Alternatively a 2-6% UV light with good plant cover. Your planting will require a bright LED light to encourage growth especially if you are growing live moss in your crab enclosure.
Please note the information above is a basic guide and we would always advise reading up thoroughly before acquiring your crabs There are many fantastic resources online and forums that will offer more specific guidelines care and setting up a living vivarium or enclosure.