Red Claw Crabs are becoming increasingly popular within the aquarium community.

The Red Claw Crab, also referred to by some as the "Thai Crab", is a small crab that reaches no more than four centimeters in length. They almost look like miniature versions of the edible Dungeness crab. The Red Claw Crab is often confused with the Fiddler Crab. One way to distinguish them is that the Fiddler Crab has one oversized claw. But the oversized claw is only seen in the males so this is not the best method. The best way to tell the difference is the color. Red Claw Crabs will have at least a tint of red in their claws.

The Red Claw Crab usually does well with community fish, though it has been known to chase those who venture too close. On occasion, they have been known to catch and eat very small fish. They are lively and are often seen moving about their tanks. However, they will spend a lot of time hiding under rocks and plants. They should be kept singly, as they do display aggression to other Red Claw Crabs. Some state that you can keep females in groups or grouped with one male, but it is not certain whether or not they will display some territorial aggression as well. The Red Claw Crab makes a great pet. They are said to be better pets than the more popular Fiddler Crab. It has been reported that this species does significantly better in brackish water than in low salt freshwater tanks.

The tank environment should provide many hiding places and should be well covered. Red Claw Crabs are known escape artists and will not survive more than a couple hours if they cannot return to their aquatic environment. Their water should be filtered and maintained somewhere between 72 and 77 degrees Fahrenheit (the literature has shown ranges higher and lower than this average). Like most crabs, the Red Claw Crab will go through a molting process where it sheds its old exoskeleton for a new one. They will consume their old shells to regain necessary calcium lost in the molting process. Calcium loss may contribute to limb loss commonly seen among crabs during the molting process. For this reason, most sources suggest giving them calcium supplements in addition to their regular diet during molting. Molting is a very stressful period for crabs and many die under the stress. It is very important to keep water quality high and feed them a very well balanced diet at this time. Also, the Red Claw Crab will be vulnerable shortly after its molt and care should be taken if it is kept with other crabs. The Red Claw crab appears to be omnivorous and will therefore eat most anything. They do well with any of the formulated sinking foods and enjoy vegetables, tubifex worms and freeze dried foods such as krill.

It has been reported that Red Claw Crabs prefer to breed in shallower, warmer waters. They also seem to prefer slightly brackish waters when breeding but will return to freshwater after they finish breeding.

After they have bred the female will have a pouch under her belly full of what looks like a soft jelly - this is very fragile and should not be touched. After a couple of weeks the female will give the eggs to the male and he will look after them until it is time to hatch. Hatching usually occurs after about 90 days. It should be noted that the babies are capable of pinching just like adults, so handling is not advised. Babies do well on a variety of foods including crushed bloodworms and crushed brine shrimp. Broken up formulated crap food works well too.