The Thai Micro Crab is a fully aquatic, extremely small freshwater crab native to a single river system (the Tha Chin river) in Thailand. They are exceptionally peaceful and lack standard defensive capabilities. Instead of hunting, they use tiny hairs on their claws to catch detritus and filter-feed biofilm. Due to their miniature size and incredibly shy nature, they must be kept with peaceful nano tank mates (like Neocaridina shrimp) or in a species-only setup to prevent predation.
At a Glance
Tank Requirements
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Water Parameters
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Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard
The standard Thai Micro Crab. Best kept in groups in densely planted tanks. They are highly nocturnal and will spend most of the day hiding among roots (especially floating plants like Water Lettuce) and leaf litter.
Same care requirements as the base species
Also known as: Wild Type
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🟢Ideal Tank MatesThai Micro Crab Care Guide Summary
The Thai Micro Crab, scientifically known as Limnopilos naiyanetri, belongs to the Invertebrates family group. Adults reach a maximum size of approximately 1.5 cm and have a depressed body shape with a slow growth rate. Classified as peaceful, this species primarily occupies the bottom zone of the aquarium and produces a low level of biological waste.
To thrive, the Thai Micro Crab requires a freshwater only aquarium with a minimum volume of 19 litres and a tank length of at least 30 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 6.5–8 and a general hardness of 6–15 dGH. A low water flow is preferred. An aquarium test kit can help you monitor these values.
Due to its specialist needs, the Thai Micro Crab is best suited for fishkeepers who can provide a carefully planned setup. The Thai Micro Crab is typically available in one standard form.
Thai Micro Crab Habitat Setup
When setting up an aquarium for the Thai Micro Crab, a low water flow best suits their natural preferences. Because this species occupies the bottom zone, the aquarium layout should prioritise sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include leaf litter or blackwater tannins to replicate their natural soft-water habitat, dense planting to provide cover, break sightlines, and reduce stress, and floating plants to diffuse overhead light and create shaded areas.
Thai Micro Crab Compatibility Notes
Classified as peaceful, the Thai Micro Crab is adaptable and can be kept singly or in a small group, offering flexibility when planning a community tank. When choosing tankmates, boisterous or fast-moving tankmates may cause this species undue stress. Selecting tankmates that favour different water layers from the bottom zone can help reduce competition and territorial overlap.
Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Thai Micro Crab.
5 Gallon
10 Gallon Standard
15 Gallon Standard
20 Gallon High
20 Gallon Long
29 Gallon Standard
Show 27 more tank sizes
Frequently Asked Questions About Thai Micro Crab
How big does Thai Micro Crab get?
Thai Micro Crab (Limnopilos naiyanetri) typically reaches a maximum adult size of approximately 1.5 cm. They have a depressed body shape and a slow growth rate.
What tank size does Thai Micro Crab need?
A minimum aquarium volume of 19 litres and a tank length of at least 30 cm are recommended for Thai Micro Crab. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Thai Micro Crab need?
Thai Micro Crab thrives in freshwater only conditions with a temperature range of 22–28°C, a pH between 6.5 and 8, and a general hardness of 6–15 dGH. A low water flow is preferred.
Is Thai Micro Crab peaceful or aggressive?
Thai Micro Crab is classified as peaceful with an aggression score of 0 out of 10. They are generally well-suited to peaceful community tanks.
Can Thai Micro Crab live alone?
Yes, Thai Micro Crab can be kept singly or in a group. They are flexible and adapt well to both setups.
Does Thai Micro Crab have any special tank requirements?
Yes. Thai Micro Crab benefits from plants - densely covered, plants - floating, and leaf litter/blackwater in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Similar Species
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