There is nothing quite as vibrant and purple as seeing your first Vampire Crab (Geosesarma dennerle). These ideal freshwater crabs are suited for the aquarist hobby and have a whole lot going for them despite their terrifying name.
Are they bloodthirsty creatures that may creep out of the tank at night and crawl to your room looking for their next meal? In a word, no.
There is nothing scary about these crustaceans that should put you off taking a chance on keeping one in your home. Feel free to invite one into your gang, and you will be rewarded with one of the most stunningly vibrant creatures in the hobby.
Found natively in the Indian Ocean, you can spot them in Asia and the Western Pacific. They are a relatively new discovery as recent as 2006. They are semi-terrestrial, adding to their intrigue besides their colloquial name.
Since they are newer to the hobby, there can be a fair amount of misinformation out there regarding this unusual species.
They are not necessarily for the beginner, however, so we will cover their requirements, and then you can decide if you might be suited to taking care of a couple of vampires without too much trouble.
Let’s take a gander at the nightcrawler, who are perhaps a little misunderstood thanks to their name, and see if we can’t tempt you to let your guard down and be the crypt keeper of this littlest of vampires without wings.
Vampire Crab Behavior
While we don’t buy that the Vampire Crab got its name from being a primarily nocturnal creature, it probably adds to the allure.
Most of the time, they will hide during daylight hours only to emerge when darkness descends. At this point, they will start to get active and rustle around in your tank opening time in both water and on land.
As these crabs are semi-terrestrial, your tank will need to accommodate this trait and cannot be a fully submerged substrate tank suited to fish.
Sometimes these crabs will just be lazy and not move from one spot for hours, but do not let that fool you into thinking that they are injured or ill. This is just how they roll.
As all invertebrates and crustaceans do, you can expect your crab to molt numerous times. This is frequent as a juvenile then gradually changes to a monthly occurrence. We recommend leaving the shell in the tank in case they consume it as it helps provide the nutrients that calcify their new shell. Remove only if you don’t see your crab getting very actively involved with it.
Vampire Crabs enjoy being discreet and like to hide after molting when they are understandably at their most vulnerable. As we will discuss with tank requirements later, sand is preferable as when they are freshly molted, they will often enjoy burrowing into the substrate for protection and some ‘me-time.’
An important point to note in this behavioral section is that Vampire Crabs are not the most compatible of creatures. They are known for being quite aggressive towards other crab species and indeed any creature of a smaller size like shrimp or fish. Should you choose to have multiple Vampire Crabs, they should get along just fine.
Vampire Crab Lifespan
If you cater to the needs of your Vampire Crab, you could expect them to live for up to 2 – 3 years. The quality of their tank conditions will impact their lifespan, as always, so you can expect a longer life if you meet their requirements meticulously.
We will discuss more on tank requirements a little later in this article.
Vampire Crab Appearance
Hands down, the biggest reason these crabs are high on the acquisition agenda for many in the hobby is down to their outstanding and striking looks.
The first time you see one, they definitely make an impression that lingers. They are incredibly vibrant, and given that their main body color is a rich purple, they almost look unreal or too good to be true.
Parts of the body may run so dark as to appear black, but there may also be white spotting on the shell which resembles a starry sky. Most certainly a species deserving of a name evoking a creature of the night.
Their eyes are on stalks like most crabs, and they happen to be a blindingly brilliant yellow, which only adds to their vampire namesake.
Interestingly, given that they have such a polarising name that evokes fear and terror, they only manage to achieve the diminutive stature of 2 inches in size full width. Their main carapace is only an inch, so they really are not very big and barely register as a handful.
We think you’ll agree this is a vampire anyone can handle!
They do have pincers, though, and although they can do the job when it comes to hunting, they are unlikely to cause you any harm or problems when it comes to managing them.
Males possess slightly larger pincers than their female counterparts, and they also happen to be lighter in purple tone.
Vampire Crab Habitat And Tank Requirements
Since these crabs are normally found living on the edge of freshwater rivers and lakes, they need access to both land and water in their setup.
They prefer dense vegetation on both land and water, so the option of using a paludarium is ideal for these crabs.
In order to give them a maximum lifespan, you will need to replicate their wild habitat as best as possible.
Tank Conditions
When it comes to deciding the ratio of space allocated to land and water, you should aim for 80% land and just 20% water.
With such a small proportion of water within the tank, it can be difficult to keep clean and well cycled.
Filtration is necessary to keep the water clean, and you’ll want the temperature to stick to between 70 – 82ºF and a pH of 7.5 – 8.0.
Water changes should happen at least monthly, and you should be aware that these crabs are sensitive to changes in their environment, whether that be on land or in the water.
Your plant matter that decays or dies off will be eaten by your Vampire Crabs, but they won’t disturb or destroy healthy plant matter.
They will be happy with a variety of plant species, and they will enjoy decor like rocks and driftwood to clamber over and hide behind when the mood suits them.
Humidifiers are a nice touch as they prefer 75% humidity on land, and this will add to their comfort level.
Vampire Crab Tank Size
The minimum tank size for 1 – 4 Vampire Crabs would be a 10 gallon one, and for every additional one, you should add 3 – 5 more gallons.
Crabs can be stressed by overcrowding, though, so don’t push to have too many at once and see how they settle in.
Choosing Tank Mates For Vampire Crabs
Ideally, you should just keep Vampire Crabs amongst themselves. They will act aggressively towards other crab species and can harm or eat smaller fish species.
If you have a large enough tank that you can provide an adequate amount of gallons of water for smaller fish species, these would be some good ones to try:
- Guppies
- Cherry Barbs
- Zebra Danios
- Neon Tetras
- Larger species of snails
- Amano Shrimp
- Ghost Shrimp
- Cherry Shrimp
- Bamboo Shrimp
How To Feed Vampire Crabs
Vampire Crabs are known as omnivores in the animal kingdom.
Normally Vampire Crabs will use their claws to bring substrate to their mouths in the wild as they scavenge as most crabs are wont to do.
Meats are an important source of protein, and you can even include things like chicken, fish. Don’t forget to include sources of calcium and include a few cuttlefish bones into the tank for them to nibble on (usually found in the bird section in pet stores).
Proteins like bloodworms, brine shrimp, larvae, and earthworms always go down a treat. Grasshoppers, crickets, and plant detritus are eagerly consumed. They also won’t turn down flakes, algae wafers, or specialist pellets either.
Vampire Crabs will happily eat most foods you add to their tank but ensure you include enough variety to keep them eager to feed and avoid boredom. Spinach, peas, and broccoli are always welcomed.
Ideally, you should feed your crabs once a day and keep varying your food sources to give them an enriched diet.
Vampire Crab Common Diseases And Illness
For Vampire Crabs, the most common issues that affect them are things like parasites, fungal infections, and bacterial infections if they do get sick. This doesn’t tend to happen often, but it’s worth mentioning things to look out for here.
Shell damage can indicate that they are lacking in the minerals and elements crucial to creating a healthy exoskeleton. As a crustacean, this needs to be firm and secure, or else it renders the specimen vulnerable and at risk of health issues and disease.
Vampire Crabs are not susceptible to major freshwater fish illnesses like Ich or Fin Rot (for obvious reasons, on that one), but they can carry the pathogens and infect other members of your tank community.
Always keep the tank clean to avoid the possibility of bacterial or fungal infections, especially when it comes to water quality. Cleaning the water portion of the tank and keeping an eye on the chemistry is just as important, even if it only makes up 20% of the surface area of your habitat. Otherwise, it becomes a breeding ground for bad things to happen or proliferate.
You should also be aware that copper in any form will poison your crab, so never allow them to be vulnerable to that element in any capacity. Some chemical treatments suitable for fish tanks may therefore not be suitable in your situation if you have Vampire Crabs. It will likely kill your population of these fascinating creatures.
How To Breed Vampire Crabs
Breeding Vampire Crabs is not well understood. There is much to be researched on this topic, but there are some basics that we do know.
They reach sexual maturity at around six months of age. The male will climb on top of the female and fertilize her eggs which she will then carry around for nearly a month after that. Usually, she will carry anywhere from 20 – 80 eggs per breeding period.
Unlike most fish, when crab hatch, they are fully formed little critters, albeit a tiny version of their mature selves. They are quite capable from the get-go and very independent about to go on about their business without too much parental interference.
Ideally, if you manage to get a breeding pair, you should separate the parents from the newly hatched crabs as they may otherwise be consumed. Sadly this seems to be the aquatic way; there isn’t much in the way of a parental attitude like we tend to observe on land or at least with mammals!
Conclusion
These crabs are an irresistible option for those in the hobby who are looking for something decidedly different with a high-impact look.
Their stunning purple hue coupled with electric yellow eyes on stalks render this species rather mesmerizing to observe, even if they aren’t the most mobile or active creatures in the tank.
They are definitely a show-stopping specimen to show off.
And who doesn’t want to say they own an actual ‘vampire’? You wouldn’t be lying if you said you did, so why not make the most of the opportunity?
Keep a bag of O-Negative in the house if you want to intimidate any of your guests; we guarantee they will be impressed with your heroism at taming a real live vampire.
