African Rainbow Crab - Cardisoma armatum
The Rainbow Crab is also commonly known as the Patriot Crab due to its colors.
They are found in both freshwater and brackish water conditions in their habitat so some salt doesn't hurt.
They do require land as it is not a fully aquatic crab. A 50/50 setup of land and water would be preferable with some area with sand so they can burrow.
These crabs love to eat fruits and veggies along with just about anything else (variety is key to good health).
Current size from left to right (far end of one set of legs to the other) is around 2.5-3" at the moment.
Fully grown, they reach about 3-6" on average in aquaria though some have reached 8".
Also known as the Soapfish Crab, Indigo Crab, Land Crab or Tricolor Crab.