Freshwater Aquarium Crabs
Freshwater aquarium crabs can be a great addition to your tank. It is important to choose the correct crabs for your aquarium and to understand how their needs vary from other creatures in your fish tank.
The first thing that you need to do is to ensure that you select a crab that is appropriate for your aquarium. Some aquarium websites (and indeed many pet-shops) misunderstand crab requirements in two major ways:
- Selling “aquatic crabs” for fully submerged environments, when in fact the crab in question is not aquatic, and needs significant amounts of dry land
- Selling crabs as “freshwater aquarium crabs” when in fact they need brackish water.
Below we highly 5 crabs that are great for freshwater aquariums. We’ll then finish by pointing out some crabs that you should not consider for your freshwater aquarium crab.
Freshwater Pom Pom Crab
Freshwater Pom Pom Crabs (ptychognathus barbatus) make for an interesting addition to your aquarium. They are relatively small (growing to less than 1.5 inches in width) and are not known for being aggressive towards other tank-mates.
Not much is know about this freshwater aquarium crab. They can be found naturally in a number of regions around the world including Africa and Asia. Their name comes from the pom pom like filters on the end of their claws.
Panther Crab
The Panther Crab (parathelphusa pantherina) is a freshwater crab that originates from Indonesia. More specifically it is from Lake Matano on the Indonesian island of Sulawesi. It is an endangered species of the Gecarcinucidae family.
Lake Matano is warm, with an average temperature of around 84 degrees Fahrenheit (29 degrees Centigrade). Further, it has a slightly alkaline pH of 7.4. The Panther crab is often found concealed under debris and tree roots. As a result of this, you should ensure that your aquarium has plenty of hiding places. An area where they can emerge from the water would also be preferable.
The Panther Crab has gets its name from its yellow coloration with dark spots. They may have tinges of red in their legs and claws. Expect them to live to approximately 5 years old.
These crabs can grow in excess of 3 inches in size. As a result they will require a larger aquarium. A minimum of a 30 gallon fish tank would be ideal. If you intend to keep more than one crab in your tank, consider a much larger tank. This is especially true if you plan to get 2 (or more) males as they can be quite territorial. They may also be moderately aggressive towards other tank-mates – so choose their companions carefully!
Thai Devil Crab
Thai Devil crabs normally grow to between 2 and 3 inches in width. Expect them to live to around 5 years in an aquarium, although they have been known to live longer in the wild.
Contrary to their name, these freshwater aquarium crabs are docile and are a great option for community aquariums. It is preferable to ensure that they are able to access an area of dry land within the tank.
Thai Devil Crabs are omnivores. They eat a range of plants, in addition to algae, fish and insects. One thing to bear in mind is that they are relatively active. Ensure that they have sufficient space to roam the bottom of your tank – where they will do a great job of scavenging food.
Thai Micro Crab
Also known as the False Spider crab, the Thai Micro Crab is… unsurprisingly small! It often measures just 1 cm in width. These crabs are often a gray / brown color and are peaceful crabs. They tend to hide a large percentage of the time and are not well suited to more aggressive tank mates.
The Thai Micro Crabs are also sensitive to changes in their environment. Adding them to a stable tank environment is therefore recommended. Ideally the water flow in the tank should also be moderate to low.
Matano Crab – Freshwater Aquarium Crab
As you may have guessed, the Matano Crab originates from Lake Matano in Sulawesi, Indonesia. These crabs are known as syntripsa matannensis. If you want an especially visual display, consider the Purple Matano Crab.
To date, Matano crabs have not been extensively studied. One thing we can safely assume, is that they will prefer warm water (around 84 degree Fahrenheit) and a pH of around 7.4. This will mimic the natural conditions in Lake Matano.
If you can get your hand on them they are a very interesting freshwater aquarium crab.
Vampire Crab
Vampire crabs are of the Geosesarma Genus. They are so called because of their yellow eyes and their often impressive red or purple coloring. Vampire crabs are small (often smaller than half an inch across) and so are a viable option if your tank is small.
At times it can be difficult to source Vampire crabs for your freshwater aquarium. But if you can find them they can make for impressive pets. They are omnivores and will do best with being fed a range of foods.
One thing to not is that Vampire crabs are not fully aquatic! So although they do great in freshwater aquariums, they do need to be able to access “dry land” within the tank. Ideally around 50% of the tank should be accessible to them above the water line. As long as you provide this, they can make for incredible, visually appealing pets.
Non Freshwater Aquarium Crabs
Brackish crabs can sometimes be confused for freshwater aquarium crabs. This is because their intermediary environment has been freshwater. They will, however, struggle to live a healthy life if they are kept in freshwater over the long term.
Fiddler Crab
Fiddler crabs, sometimes known as a calling crab, are not freshwater aquarium crabs. They do, in fact, prefer brackish waters. They are known for their distinctive claws. One is of size proportional to its body. The other is ridiculously huge!
Red Claw Crab
Red Claw crabs are often seen in freshwater aquariums. They are, however, naturally suited to brackish water. If you want to keep a crab (and for it to have a long and happy life) don’t add it to a freshwater aquarium. Instead set up and tank that has brackish water!
If crabs aren’t quite your thing there are plenty of other options. Freshwater aquarium snails and freshwater aquarium catfish both make for interesting options in your freshwater aquarium.