There are many lovely different animals that you can keep in aquariums. If you’re anything like me, though, then the odd and unusual animals have special appeal.
Cue the panther crab, a medium-sized, fully-aquatic crab, a species of freshwater crab, that’s ideal for beginners. With its leopard-like spots and beautiful coloration, this species is a sight to behold.
Strangely enough, despite its bold coloration and ease of care, this crab is often overlooked as an aquarium inhabitant. Let’s take a closer look at how to care for this lovely species.
Panther Crab Facts & Overview
- Scientific Name: Parathelphusa pantherina
- Lifespan: two to five years in captivity; up to ten years in the wild
- Size: three to five inches
- Habitat: Fully aquatic
- Origin: Sulawesi, Indonesia; native to Lake Matano and surroundings
- Minimum tank size and tank type: 20 gallons or more; Aquarium or paludarium
- Temperature and pH: 77-86°F; 7.5-8.5 pH
- Diet: Omnivorous
- Behavior: Territorial, and sometimes aggressive
- Care level: Beginner
A few key points about panther crabs:
- They’re easy to care for, but require a high-protein, high-calcium diet
- Aggression varies from animal to animal, but they’re all highly territorial, so best kept in a species-only aquarium
- They rarely get sick, but have short lifespans in captivity
- You can breed them, but it will be more by chance than intention
- Ensure that the tank contains plenty of crab-proof plants and decor
- These crabs are fully aquatic, freshwater animals, that don’t need land
Panther Crab Appearance
The panther crab, Parathelphusa pantherina, is a small to medium-sized crab that can reach lengths of between three and five inches.
It’s a striking species that has a light silvery-tan base coloration, covered with reddish brown, and darker brown to black spots.
It has the smaller pincers typical of crabs which prefer foraging to hunting. The pincers have a reddish-brown upper side and may have bright red tips, depending on where the crab originated.
Panther Crab Natural Habitat
Panther crabs naturally inhabit a part of Sulawesi Island in Indonesia. Mainly, they live in and around Lake Matano, but they have been recorded in areas south of the lake as well.
To keep these crabs as well as possible, I’d recommend mimicking their natural habitat as closely as possible. Let’s take a closer look at the lake these animals call home.
Indonesia is a country with a fair bit of vegetation, and the area around Lake Matano features some impressive forests, as does the lakeshore. The lake’s floor is quite sandy, with a few rocks thrown in, and a fair bit of algae and aquatic vegetation.
Thanks to the surrounding forests, and the nutrient runoff from them, the lake is highly fertile, so water-loving plants grow here with ease. The lake also contains a lot of driftwood, yet another gift from the plentiful forests.
Indonesia is almost entirely tropical and, as a result, maintains mild to warm temperatures all year round. This means that Lake Matano has relatively warm water with an abundance of fish, invertebrates, and other aquatic creatures. The lake has an average pH of between 8.23 and 9.61, meaning it’s slightly alkaline.
Now that we’ve had a look at their natural habitat, let’s take a closer look at how to translate them into captive conditions for your new pets.
Panther Crab Tank Setup
While Panther crabs are fairly adaptable by nature, you’ll get the best results if you mimic the environment they come from. Below, I’ll detail the best tank sizes, substrate, and decor to help keep your crab healthy.
The panther crab is relatively large compared to some of the other freshwater crabs commonly kept in captivity. As a result, they need a considerably larger tank with plenty of space as well. If you’re planning on keeping these stunning animals, you should aim at a tank size of at least 20 gallons.
If you’re planning on keeping more than four, add another five to ten gallons for every additional crab.
As mentioned earlier, the floor of Lake Matano is a fair mix of sand, rock, and vegetated areas. Since the lake receives a lot of nutrient runoff from the surrounding areas, even the sandy areas are quite fertile.
I’d recommend the following substrate setup for your panther crab:
- Place a layer of river stones, or medium-sized pebbles at the bottom of the aquarium, around an inch thick.
- Cover the stones with about a half-inch to three-quarters of an inch of good, high-quality aquarium sand.
- Use a high-quality planting substrate, and mix it into certain portions of the aquarium.
Following this setup will replicate their natural environment quite well. As time goes by, some of the finer substrates will infiltrate the layer of river stones, leaving some larger stones exposed. This is an intentional part of the process, so don’t put too much effort into keeping them covered.
Lake Matano is a relatively cluttered body of water, containing plenty of rock outcrops, driftwood, and vegetation. Panther crabs are relatively territorial, and using decor to break the tank into smaller areas can help.
These animals are especially fond of having hiding places, so we’d recommend incorporating plenty of caves. Other decor items to consider include:
- Pieces of rock or slate, especially in the form of slate caves
- Hardy plants like java ferns
- Floating plants
- Pieces of driftwood
Since panther crabs come from warm, alkaline water conditions, they require similar conditions in captivity.
Since Lake Matano contains many soluble minerals, the water hardness is quite high (around 5-7). You need to replicate this by using water that isn’t too soft, or hardening soft water.
The lake has a relatively alkaline pH of around 8, so I’d recommend keeping the pH level between 7.5 and 8.5.
They also need warm conditions, of around 76-82°F (24-28°C). Otherwise, as long as you keep the water clean, they should be relatively easy to care for.
Do Panther Crabs Need Dry Land?
Unlike many of the crabs kept by aquarists, Panther crabs are fully aquatic. While you can keep them in a paludarium (a tank with half land and half water), if you’re so inclined, it isn’t necessary.
Behavior and Tank Mates
Panther crabs, while generally territorial, aren’t terribly aggressive. That said, many different aquarists have had vastly dissimilar experiences with them.
They’re generally quite calm, and will spend the days resting. They’re nocturnal, which means they’re most active at night. However, you may see them at any time of the day, combing the substrate for morsels of food.
When fed properly, with a well-balanced and complete diet, panther crabs may not attack tank mates. They generally prefer foraging for food to hunting for it. But, they’re highly opportunistic, and won’t hesitate to eat anything they can catch with ease.
Many aquarists like to keep panther crabs on their own, as it eliminates any risk of their eating tankmates. However, some aquarists have had great success with keeping these crabs with other fish.
Naturally, their preference for alkaline water somewhat limits your choices. You also don’t want to keep them with other bottom dwellers, or slow-moving fish. This means that it’s best to avoid species like:
This is mainly as a safety precaution, in case one of your crabs does want to go on a hunting spree. Most aquarists who keep panther crabs in a community keep them with surface and mid-dwelling fish that move quite quickly, such as:
- Larger tetras
In the end, it comes down to how adventurous you are, and whether you’re willing to accept the loss if something goes wrong. Personally, I’d recommend keeping them in a species-specific setup, but I understand the appeal of a community.
Bear in mind that:
- Panther crabs are most active while fish are asleep, making the fish easy targets
- Crabs molt as they grow, and may be vulnerable to predation from fish while doing so
If you do decide to set up a Panther Crab community tank, use plenty of decor so that the area has many visual demarcations. This will help cut down on the crabs’ territoriality.
The Panther Crab is a highly omnivorous creature and requires both vegetation and protein in its diet. While you can use bottom feeder pellets as a part of their diet, you’ll need to supplement that with plenty of additional items.
We’d suggest using prepared products like:
- Sinking invertebrate pellets
- Algae wafers
- Veggie wafers
- Brine shrimp
We’d also work with plenty of fresh ingredients, such as:
- Blanched lettuce
- Blanched green beans
- Lightly cooked carrots
Live foods are also important, and sinking live foods are an excellent choice, including:
- Tubifex worms
- Ghost shrimp
The key is to provide a diverse diet, with around 75% animal protein. You might have to play around a bit till you find the menu that works best for your crabs.
Finally, crabs need a high-calcium diet. Like most crustaceans, they molt to grow, which takes a lot of calcium. Take care to provide them with plenty of high-calcium foods like:
- Cuttlefish shell (crabs can nibble on it as a calcium supplement)
- Snails (lots of calcium in snail shells)
- Shrimp and prawns
Do Panther Crabs Chew Everything?
Yes, like most species of crab, panther crabs are omnivorous, and likely to chew anything they can get their hands on (no, wait, pincers). From plants to slow-moving tankmates, very little is safe from a hungry crab.
That’s why you should only use the hardiest plants, and floating plants, if you’re planting your aquarium. You should also keep them alone if you don’t want to run the risk of losing tankmates.
Their omnivorous nature has an upside, however. For the most part, you won’t need to worry about there being leftover food in the aquarium. These animals consistently comb the substrate to remove food particles.
Panther crabs are relatively easy to care for and require very little supplemental care beyond what you’d usually put into your aquariums.
The main exception is, considering their high-protein diet, you’ll need to do a 25% partial water change weekly, and a 50% partial water change once a month. We’d recommend vacuuming the substrate every two weeks, just to ensure that no food gets left behind.
Apart from that, using a high-quality platform filter, in conjunction with plenty of aerators, should keep the crabs fighting fit.
These crabs would also benefit from a full-spectrum light, set on a timer. 12 hours with light, and 12 hours without, will give them the day-night demarcation that they need.
Panther Crab Health
Panther crabs don’t tend to get sick easily, though they often don’t live as long in captivity as they would in the wild. There are three main things that you might have to deal with, which we’ll cover below.
In some cases, when a crab molts its new shell or part thereof, may be soft. The shell is always soft for the first 12 hours or so after ecdysis (molting). However, if the shell doesn’t harden properly within 48 hours, or parts of it don’t, your crab has softshell.
Softshell happens when your crab doesn’t get enough calcium. It’s vital that, when a crab molts, you don’t remove the old shell. The crab desperately needs the calcium and chitin from the old shell to help build up minerals for future shells.
Because crabs get larger with every molt, they also need additional calcium in their diet. Ensure that you feed your pets plenty of snails, crustaceans, and other calcium-rich foods to help them with their shell-building.
If you encounter a case of softshell, there’s not a lot you can do till your next molt. If you only have one crab in the aquarium, without any companions, that’s fantastic. If you have it in a single-species group or community, it’s best to (very carefully) remove it to another aquarium.
Until such a time as the crab molts again (this may take several months), feed it plenty of calcium-rich foods, and mineral-rich foods. Doing so will help it build a reserve so it can molt properly and form a hard shell. Feeding it more regularly should also help it to get to the next molt sooner.
Once it has molted again and has a hardened shell, you can move it back to its home.
It’s not unusual for panther crabs, and crabs in general, to lose the occasional limb in a fight with other tank inhabitants or some other form of accident.
Luckily for the crab, and you, crabs can regrow lost limbs and pincers. Simply ensure that the crab receives plenty of high-calcium foods until it has its next molt.
Over the course of several molts, the crab will regrow a full limb. In exceptional cases, the limb will regain a similar size to what the crab had. In most cases, however, the new limb will be slightly smaller than the original.
Take note, however, that crabs can’t regrow missing organs like eyes. Once these body parts are lost, they’re lost forever.
Parasites are the final health problem you’re likely to face with your panther crabs. Due to their diet, which consists largely of animal protein, crabs can be susceptible to parasites like gill fluke.
Unfortunately, there aren’t many options for treating parasites in invertebrates. If you discover this kind of problem with your panther crabs, I’d recommend consulting a vet with expertise in this field.
While breeding panther crabs in captivity isn’t the easiest thing to do, it’s certainly possible. The most important things to bear in mind are:
- Panther crabs are territorial, so create many visual barriers when trying to breed them.
- The water must be clean, and the conditions must be exactly as they prefer.
- You need to maintain the correct ratio of males to females.
Sexing Panther Crabs
The number one most important thing when trying to breed panther crabs is to maintain the correct ratio of males to females. Preferably, you want no more than one male per female.
This is because females release pheromones when they’re ready to breed. If there are too many sex-crazed males running about, they can damage or kill the female.
But how do you tell the difference between males and females? Let’s take a look. Males and females both have a portion at the rear of the crab’s underside. It’s called a telson and varies significantly in shape between males and females.
In females, the shape is broad and covers most of the bottom of the abdomen. In males, the shape is much narrower, and sharply triangular, with a lot of extra space around it.
As stated above, panther crabs aren’t the easiest animals to breed in aquariums. Mainly because they’re highly territorial, and we don’t know what their breeding triggers are.
If you have a good setup, and your crabs are happy, then the females may produce pheromones when they’re ready to breed. The pheromones will attract the males, who will fertilize the female’s eggs.
As the female lays the eggs, she will scoop them up and place them inside her telson, also called an apron. This is what is known as berrying. The female will continue to carry the eggs until they hatch.
I’d recommend removing the other crabs, or the berried female, to another aquarium. After the baby crabs hatch, and the female releases them, move her back to the main aquarium. This is because panther crabs are cannibalistic and will happily eat the young crabs.
Raising Panther Crab Young
If your panther crabs have successfully bred, you want to maintain the young at all costs. This means providing plenty of food in small portions. Preferably, about as much as they’ll eat in a few moments, four or five times a day.
As the crabs grow, you should have several aquariums to split them into. This will help prevent territoriality and cannibalism, keeping losses to a minimum. Ensure that each tank has a lot of decor, and many hiding places, so the crabs have space to set territories.
Young panther crabs may eat the same foods as adults but in smaller amounts. Remember to offer sufficient calcium.
Buying a Panther Crab
Panther Crabs aren’t cheap, but I’d say they’re relatively inexpensive for a freshwater aquarium crab and may cost between $20 and $40 per crab.
The main cost to bear in mind when buying one isn’t the cost of the crab itself, but rather the cost of feeding it. While panther crabs are medium-sized, they have voracious appetites and require plenty of protein and calcium.
Meeting all their dietary requirements may cost several dollars per day. While that isn’t a huge price to pay, you’d be wise to see if it fits into your budget before buying one of these crabs.
Choosing a Panther Crab to Buy
If you’re determined to buy a panther crab, you ought to know exactly what you’re looking for.
After being put through the stress of transport, water changes, and a new environment, not all the crabs you see for sale may be in good condition. Some may have been damaged, and others might be suffering from shock.
So, when you’re trying to choose a crab from the display tank, look out for:
- A crab with active movements, and plenty of energy
- A crab that has bright coloration, and isn’t pale or discolored
- A crab that isn’t missing any of its limbs or appendages
- A crab with a good appetite
Lethargy, discoloration, and lack of appetite may all be signs of a more significant problem. Look for a crab that looks entirely healthy, so you get full value for money.
Panther crabs are beautiful, fascinating, and lots of fun to have around. If you’re looking for something unusual, and with a great personality, this species is something to consider.
They’re territorial, and sometimes aggressive, so it’s best to keep them on their own, or with others of their kind.
But, they’re easy to care for and highly entertaining so I’d definitely recommend them. Just bear in mind that they need a high-protein, high-calcium diet which can be costly.
If you want to learn more about having crustaceous in an aquarium, see also our artilce about pet lobsters.
I hope you’ve enjoyed this article about Panther crabs, and that it has answered all your questions. If I’ve missed something, that you’d like to know, feel free to reach out. We’d love to hear from you.
About the author
Hi, I’m Johanan! I love animals of all shapes and sizes, but especially fish. I’ve gone from working at a pet store as a teenager to keeping and breeding Bettas and other fish at home. My passion for fish is endless!
You can find my articles here.