Quick answer: vampire crabs are small omnivores from the forest floors of South-East Asia. In the wild they eat mostly rotting plant debris, with worms and insects when they find them. At home, feed a little every day or two in the evening, on the land side of the paludarium: a protein food such as insect granules, bloodworm or a piece of dried shrimp on some days, and plant food such as a crushed pea on others. Keep leaf litter down for them to pick over and a dish of calcium in all the time, and lift out whatever is left the next morning.
We do not sell vampire crabs, but most of what they eat is on our dry goods shelf, and the springtails many keepers use as live food are among the cultures we sell. This guide covers what vampire crabs eat in the wild, what keepers feed, which of our foods fit and what to check on a label. It is a food guide, not a care sheet.
What Vampire Crabs Eat in the Wild
"Vampire crab" is a trade name for small, semi-terrestrial crabs of the genus Geosesarma. They live on damp forest floors in South-East Asia, close to fresh water, and spend most of their lives on land.
The one study of their wild diet we found looked inside the stomachs of vampire crabs collected at two sites in the Menoreh hills of Java, a snake fruit orchard and a rocky cave cliff beside a stream. Of the 25 crabs with food inside, every one held plant debris and fragments of leaf, 24 held wood, and two held worms. By volume, debris made up about three-quarters of what they had eaten and worms about a fifth, though only two crabs had eaten any. The researchers class vampire crabs as omnivores that lean towards plant food, living mostly on decomposed plant material with worms as an occasional extra.
Notes on other species point the same way. One species recorded in Singapore is described as mainly a plant-eater, a Thai species described in 2023 eats insects and plant parts, and another species climbs into pitcher plants, where it has been reported taking the drowned prey. A vampire crab is an omnivore: plant debris makes up the bulk of its diet, and it takes animal food when it turns up.
What Keepers Feed
Care sheets from crab specialists and aquatic shops agree on a mix. On the animal side they name bloodworm, small insects, shrimp and insect-based dry foods; on the plant side, soft vegetables, a little fruit and leaf litter. Most add a calcium source as well.
They differ on the balance. A crab specialist writing in a UK fishkeeping magazine calls vampire crabs omnivores but says meaty prey makes up much of their diet. That sits against the wild stomachs above, which were full of plant debris. Different species may simply eat differently, which is one reason the name on the label matters (see the note on trade names below). Our reading: offer both sides of the diet and watch which foods your crabs clear.
How Often and How Much
Care sheets range from a little every day to three or four times a week, and they agree on the rest: small portions, and nothing left to rot. Vampire crabs feed at dusk and through the night, so put food out in the evening and lift out whatever is left the next morning.
Feed on the land side of the paludarium, in a small, shallow dish or on a flat piece of bark, and keep food out of the water. The crabs drink from the water and climb into it, and several care sheets say they need it to moult, so food left to rot there fouls the water they depend on.
Keep the pieces small. The wild study notes that vampire crabs have small mouths: they tear food apart with their claws and eat what fits. With any food that is new to your crabs, start with less than looks right and check what is left in the morning.
Protein: Insect Foods, Bloodworm, Shrimp and Daphnia
Our insect granules are the closest thing on our shelf to the insect-based dry foods care sheets name. Mealworm meal is the first ingredient, with herring meal behind it, and the label gives 44% crude protein, 2% crude fat and 6.5% crude fibre. At 1 mm, the granules need no breaking up.
Bloodworm is on most vampire crab care sheets. Our freeze-dried bloodworm is the larvae of non-biting midges, dried whole, at 55% crude protein. In damp air it takes up water and softens within hours, so offer a few at a time and clear what is left by morning. Bloodworm is a recognised allergen for a small number of people, so tip it out rather than pinching it out, and wash your hands after feeding.
Our dried shrimp are whole shrimp, sun-dried, with nothing added, at up to 62% crude protein. Because they are whole, the shell comes too, and a shrimp's shell is chitin hardened with calcium. Break one into small pieces for vampire crabs.
Our dried daphnia are whole water fleas, freeze-dried, with nothing else in the bag, at 50% crude protein. They are the lightest of these foods, so a small pinch goes a long way. In a warm, humid tank they take up moisture and can grow mould within a day, so clear them by morning too.
Rotate these rather than leaning on one. Care sheets also list fish flakes, but our tropical fish flakes are not in this guide, for the same reason as in our guide to what hermit crabs eat: their ingredient list includes antioxidants without naming them, so we cannot rule out ethoxyquin, a preservative used in fish meal.
Plant Food and Leaf Litter
For the plant side, care sheets name soft vegetables such as courgette, spinach and carrot, with a little fruit now and then. Our freeze-dried garden peas have a one-line ingredient list: garden peas. Crush one into small pieces; they soften as they take up moisture, so nothing needs soaking first. Fruit goes over quickly in a warm, humid tank and draws fruit flies, so keep it to a small piece and lift it out by morning.
Leaf fragments turned up in every stomach in the Java study, though in small amounts, and leaf litter on the land side gives the crabs something to pick over between meals. Our broadleaf and bamboo leaf litter is dried British hardwood leaves with tougher bamboo leaves folded through, and the bamboo decays far more slowly. As with any leaves going into a vivarium, bake or freeze them first: about 100°C for at least 30 minutes, or at least a week at -18°C or colder. Keep our leaves on the land, not in the water.
Live Food: Springtails and Small Insects
Vampire crabs hunt. Care sheets list small live insects such as fruit flies, small crickets and mealworms, and the magazine article above describes live crickets being hunted down in a flash. They take springtails too, and springtails do two jobs in a paludarium: they are a live food the crabs catch, and a cleanup crew that works over leftover food and soft mould in the damp substrate, a help rather than a cure. Young crabs are only a few millimetres across when they first appear, and keepers raising them name springtails as food small enough for them.
Our orange springtails suit the job. They are larger than the standard white springtail, they mostly crawl rather than jump, and their colour makes them easy to see on a dark floor. Keep a culture in its own tub and tap a portion into the paludarium as live food. If you want a population to settle in the substrate as well, seed it when you set up the paludarium and add the crabs at least a month later, the same rule we give for dart frogs and anything else that eats springtails.
Calcium and Moulting
A crab grows by moulting, and its new exoskeleton is hardened with calcium. Crabs commonly eat the exoskeleton they have just shed, so leave it where it is. Care sheets add a calcium source that stays in the paludarium all the time, usually cuttlebone or crushed eggshell. Crushed oyster shell is calcium carbonate too: ours is at least 95 per cent calcium carbonate, supplied crushed with nothing added. Keep it in a small dish of its own on the land side.
In one laboratory study, two semi-terrestrial crabs, one of them from the same family as vampire crabs, both ate more of the diet with the most calcium in it. We have found no study that tests whether a calcium dish changes how vampire crabs moult, so treat it as standard keeping practice rather than a fix for moulting trouble.
Copper in Crab Foods
Crab and shrimp keepers are wary of copper, and with reason: copper dissolved in the water, as in some fish medicines and snail treatments, is toxic to crustaceans, so keep those out of a paludarium. The copper on a food label is a different matter. It is there as a trace nutrient, and crustaceans use copper in their blood, which carries oxygen on a copper-based pigment.
Many keepers still read the label and leave out foods that list copper sulphate, and that is an easy rule to follow. We have found no feeding study on vampire crabs, so we will not call any amount proven safe; the danger on record is copper in the water, not copper on an ingredient list. Our guide to feeding a shrimp tank and its bottom feeders goes into copper in more detail.
Is It a Geosesarma? A Note on Trade Names
"Vampire crab" is a trade name, not a species. Two Javan species sold as vampire crabs were in the aquarium trade for years before scientists described and named them in 2015, and other Geosesarma species still await names.
A 2026 survey of land crabs sold online by sellers in the UK, the USA and continental Europe found 23 species on sale, with five common names each covering more than one species. "Vampire crab" was used only for Geosesarma, but it was applied across several species rather than to one; "rainbow vampire crab" covered three different Geosesarma species, and "panda crab" covered crabs from two genera, Geosesarma and Lepidothelphusa. Almost a third of the listings gave no species name, and the authors point out that different species may have different dietary and care needs.
So if your crabs came with only a common name, ask the seller for the genus and, if they know it, the species. This guide is written for Geosesarma; a crab from another genus may need a different diet.
Frequently Asked Questions
What do vampire crabs eat?
They are omnivores. In the wild they eat mostly rotting plant debris and leaves, with worms and insects when they find them. At home, feed small amounts of protein foods such as insect granules, bloodworm and dried shrimp, plant food such as peas, leaf litter to pick over and live springtails, with a calcium source that stays in.
How often should you feed vampire crabs?
Care sheets range from a little every day to three or four times a week. Feed in the evening, on the land side, and lift out whatever is left the next morning.
Can vampire crabs eat fish flakes?
Care sheets list them. Read the ingredient list first: many keepers avoid foods that list copper sulphate or ethoxyquin. Our tropical fish flakes list antioxidants without naming them, so we leave them out and point you to our insect granules instead.
Do vampire crabs eat their old shell?
Usually, yes. Crabs commonly eat the exoskeleton they have shed, so leave it in the paludarium.
Do vampire crabs need salt water?
No. Vampire crabs are freshwater crabs, so they need dechlorinated fresh water, unlike a hermit crab, which needs a dish of salt water as well. UK tap water is treated with chlorine, chloramine or both, depending on where you live, so use a conditioner that says it treats both.
Do vampire crabs drink blood?
No. The name comes from their glowing yellow or orange eyes and their habit of feeding at dusk and after dark. In the wild diet study we found, their stomachs held plant debris, leaves, wood and the odd worm.
Do vampire crabs eat springtails?
Yes. Keepers use springtails as live food and as a cleanup crew. If you want the springtails to settle in the substrate, seed them when you set up the paludarium and add the crabs at least a month later.
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