A tiny, jewel-like semi-terrestrial crab — deep purple with glowing yellow eyes — that’s easy and social to keep in a humid paludarium, as long as you give it both land and shallow freshwater.
🟣 Stunning purple & gold🏝️ Semi-terrestrial (land + water)💧 Freshwater — no salt needed⏳ 2–3 years
Care difficulty
Easy–Moderate
Animal cost
£10–£25 each
Full setup
£40–£150
Adult size
2.5 cm body / ~5 cm leg span
Lifespan
2–3 years
Min. enclosure
Paludarium 45×30×30 cm+ (group)
📋At a Glance
Vampire crabs are stunning little semi-terrestrial crabs — deep violet-purple bodies, cream-and-orange markings and striking glowing yellow eyes (the source of the ‘vampire’ name). They’re small, peaceful, social and genuinely easy to keep, making a beautiful, active display in a planted paludarium. The single most important point: they are semi-terrestrial and freshwater — they need mostly land with an area of shallow fresh water (no salt, unlike many pet crabs), and they will drown if they can’t climb out. Kept in a warm, humid, escape-proof paludarium with hides, they’re a charming, colourful, low-cost colony animal.
Best for: a warm, humid, planted paludarium (land + shallow freshwater) — as a colourful, social, easy display crab.
💷Costs & Getting Hold of One
The animal
£10–£25 each (colour forms vary); best kept as a small group.
Full setup
£40–£150 — a humid paludarium, land substrate, shallow water area, cork bark/hides, plants/moss, heat, tight lid.
Ongoing costs
Low — food, occasional calcium, dechlorinator, a little electricity for heat.
Availability
Fairly easy — captive-bred stock is common (they breed readily).
These are minimums, not budgets. The low end still has to meet the animal's needs — proper UVB, a heat gradient, space and filtration are not optional extras. A vivarium alone can cost £250–£300+, and a tortoise's UVB lamp alone is often ~£100. Price the whole setup before you commit to the animal.
Buying tip: Choose active crabs with all legs and claws present and a hard, undamaged shell (avoid soft, freshly-moulted or sluggish ones). Buy a small group. Confirm they’re Geosesarma (freshwater semi-terrestrial), not a brackish/marine species.
🏠Enclosure & Where to Keep It
A humid, planted paludarium — mostly land with a shallow freshwater area — suits these semi-terrestrial crabs.
Layout
Roughly 70% land, 30% shallow fresh water — they forage on land and need water to wet their gills, but drown if they can’t climb out.
Group
Social — keep a small group; provide plenty of hides so each crab has space (males can squabble a little).
Furnishing
Cork bark, driftwood, plants, moss and leaf litter for cover, climbing and grazing; lots of hiding spots for moulting.
Escape-proof
A tight, gap-free lid is essential — they’re excellent climbers and determined escapers.
They are semi-terrestrial, not aquatic — a fully-flooded tank drowns them. Provide mostly land with shallow, easy-exit fresh water, and never keep them fully submerged.
🌡️Temperature, Lighting & Humidity
Temperature
Tropical — 24–28 °C; a low-wattage heat mat on the side/back or a warm room keeps them comfortable.
Lighting / UVB
A gentle day/night cycle; low-to-moderate light suits them and helps live plants/moss (no special UV needed).
Humidity
High — around 75–85%. Mist regularly; a well-planted, covered paludarium holds humidity well.
Bedding / substrate
A moisture-retentive land substrate (coco fibre/soil mix) deep enough to stay damp, plus moss and leaf litter; a separate shallow, dechlorinated freshwater area.
🍽️Diet, Supplements & Feeding
An omnivore/scavenger — a varied diet with some protein and calcium.
Staple
Quality sinking crab/shrimp pellets or a good omnivore food.
Fresh
Blanched vegetables, bits of fruit, and leaf litter/biofilm to graze.
Protein
Occasional frozen/live bloodworm, brine shrimp or a little fish/insect.
Calcium
Provide a calcium source (cuttlefish bone/crushed eggshell) — vital for the shell and for moulting.
Variety plus a calcium source keeps them healthy and helps successful moults; remove uneaten fresh food before it moulds.
✨Grooming, Shedding & Additional Needs
No grooming — keep the paludarium warm, humid and clean, with a calcium source. Like all crustaceans they moult to grow, and are soft and vulnerable for a day or two afterwards — leave a moulting/newly-moulted crab alone and make sure it has hides.
Don’t disturb a crab that’s buried or freshly moulted (pale, soft) — it’s vulnerable until the new shell hardens. Provide calcium and plenty of hiding spots for safe moulting.
🖐️Handling & Interaction
Not really a handling animal — they’re small, fast, easily stressed and can give a tiny nip with their claws. Best enjoyed as an active, colourful display; interact by feeding and observation.
How to handle
Avoid routine handling. If you must move one, gently coax it into a small container rather than grabbing it (grabbing risks shed limbs and stress). Wash hands before and after.
✅ Do
Keep mostly land with shallow, easy-exit fresh water.
Keep a small group with lots of hides.
Provide a calcium source for moulting.
Maintain warmth (24–28 °C) and high humidity.
Use a tight, gap-free lid.
⛔ Don't
Don’t keep them fully submerged (they drown).
Don’t use salt/brackish water (they’re freshwater).
Don’t handle for fun or grab them (shed limbs/stress).
Don’t disturb moulting crabs.
Don’t leave gaps in the lid (escape artists).
🦎Fun Facts
Named for their striking glowing yellow eyes against a purple body.
Semi-terrestrial and freshwater — they need land plus shallow fresh water, not salt.
Tiny — a body around 2.5 cm with a ~5 cm leg span.
Breed readily in captivity, with no free-swimming larval stage (miniature crabs hatch directly).
Social — they do well in small colonies.
⭐Overall Verdict
A tiny, jewel-like semi-terrestrial crab — deep purple with glowing yellow eyes — that’s colourful, social and genuinely easy in a warm, humid, planted paludarium. The golden rule is land plus shallow fresh water (never fully submerged, never salt), with hides and a calcium source for moulting and a tight lid against escapes. Get that right and vampire crabs are a stunning, low-cost, active display colony.