Temperature Range: 70 – 85 F.
Habitat: Freshwater to slightly brackish
Life Span: 2-4 years
Species: Sesarmops intermediumi
Size: up to 3”
Red semarmid crabs originate from Taiwan, China, Indonesia, and the Philippines. They are typically found several miles inland along rivers and in mangroves. In aquariums, they live in freshwater, but they must also have terrain in the aquarium as well. They will only reproduce in brackish water. Their bodies are reddish orange in color, and their legs are brown to reddish. The red sesarmid crab’s claws are cream colored. They have flattened bodies and protruding eyes.
Red sesarmid crabs need a well-structured aqua terrarium with a secure lid because they are climbers and can easily escape. You should have plenty of rocks and pieces of wood in the tank for them to climb on. They like to tunnel, so a cave or something they can tunnel through is a good idea. A good soil or sandy substrate will provide them a place to dig, and they will bury themselves in it when they molt.
Red sesarmid crabs are omnivores, and they will primarily eat algae and organic matter in the tank. However, you should supplement their diet with vegetables like sprouts and zucchini, as well as apples, pears, and bananas. They will eat mosquito larvae, earthworms, sardines, tuna, and mussels as well. They will eat most any dry food, such as fish flakes, shrimp pellets, or dried algae flakes. You can also give them cuttlebone or crushed eggshells for extra calcium.
Molting And Reproducing
Red sesarmid crabs molt and reproduce best if their water is slightly brackish or salty. Adding sea salt to the water will help. They will molt every few months, and will usually eat their own exoskeletons after molting. Breeding is not usually successful in captivity. If the female gets pregnant, she will carry hundreds of eggs for three or four weeks. Once the eggs are released, the offspring will go through several larval stages before appearing as miniature adults. The offspring are considerably at risk from predators during the larval stage.
Red sesarmid crabs should be kept in groups. Each group should ideally consist of one or two females and one male. The males are territorial, you need a big tank if you want to keep more males. They can have non-aggressive fish as tank mates. They are great climbers, and they will spend considerable time digging and climbing. They are attractive looking crabs for a hobby aquarium, and they are easy to care for.
Red sesarmid crabs are relatively easy to keep, and they are entertaining to watch. Although they live in freshwater, some salt added to the water provides them with needed minerals, and is beneficial for when they are molting.