Maximum size : 2 cm

Sulawesi Harlequin Shrimp - Caridina spongicola : Complete Shrimp Profile & Care Guide

Table of contents


The stunning Sulawesi Harlequin Shrimp (Caridina spongicola) is a unique and eye-catching freshwater shrimp that is initially shy and tends to hide until they feel secure in their surroundings. Once they settle in, their playful and social nature comes to the fore, making them a delightful addition to any community tank. These Shrimp are constantly scavenging and feeding, foraging through the substrate, rocks, and plants for algae and other small organisms. They are a fascinating species to watch, displaying social behaviours that can be pretty entertaining. Keeping Sulawesi Harlequin Shrimp is not recommended for novice shrimp Keepers as this species poses unique challenges and necessitates the establishment of a specialized system tailored to meet their distinct requirements.

Sulawesi Harlequin shrimp display a proclivity for social interaction, exhibiting a preference for the presence of conspecific companions. Such social cohabitation not only enriches their existence but also contributes to a reduced level of stress. Moreover, larger colonies tend to boast heightened activity levels, with individuals frequently venturing from their concealed habitats and engaging in conspicuous displays. Therefore, it is recommended to maintain Sulawesi Harlequin shrimp in substantial groups to foster their well-being and encourage their natural behaviours.

Decorative elements within the aquarium environment assume a pivotal role in the well-being of Sulawesi Harlequin shrimp. These adornments serve multifaceted purposes, including facilitating the proliferation of algae and biofilm, furnishing essential hiding zones, and mitigating stress levels among the shrimp population. Of particular significance is their role in facilitating the moulting process. Consequently, it is imperative to incorporate ample shaded regions, realized through the strategic utilization of materials such as rocks, PVC pipe, or plastic tunnels, to afford the shrimp a suitable sanctuary.

The Sulawesi Harlequin Shrimp is characterized by a well-developed and notably elongated rostrum. Its distinctive features include three clearly discernible transversal bands, typically reddish or dark-brown in colour, adorning the carapace. Interestingly, the first two bands often converge on the dorsal surface, forming an N-shaped configuration when viewed laterally. The body of this shrimp species may exhibit transparency or a subtle white pigmentation. Furthermore, the legs tend to culminate in red-tipped segments or remain colourless. In addition, their large black eyes are perched on red stalks, making them stand out even more.

Sulawesi Harlequin Shrimp Photos

Sexual Dimorphism

Distinguishing between male and female Sulawesi Harlequin Shrimp poses a significant challenge, as their physical appearance is almost identical. Despite diligent observation, it remains impossible to differentiate the two sexes without specialized equipment. However, the female does possess a distinctive saddle beneath the carapace that holds the eggs. Unfortunately, this saddle is only visible under infrared light, rendering it invisible to the naked eye. The shrimp's dark outer shell also further complicates the identification process.

Quick Facts

Scientific NameCaridina spongicola
Year Described2006
Other NamesCelebes Beauty Shrimp, Sponge Shrimp
Max Size2 cm
Aquarium LevelAll Levels
DifficultyIntermediate - Advanced
Best kept asGroups 10+
Diet & FeedingOmnivore
LifespanUp to 2 Years

Water Parameters

Water TypeFreshwater
pH 7.0 - 8.5
GH 4 - 8
KH 4 - 6
TDS 50 - 150
Ideal Temperature
78 - 85
25 - 29

Natural Habitat

The stunning Sulawesi Harlequin Shrimp are a unique and fascinating species endemic to Lake Towuti in the Malili Lakes system in Sulawesi, Indonesia, in Southeast Asia. These shrimp have developed an incredible relationship with an undescribed freshwater sponge of the suborder Spongillina, living on and sometimes dwelling inside its oscula. This makes the Sulawesi Harlequin Shrimp one of only two known commensal freshwater species shrimp.

In their natural habitat, these shrimp can be found hiding among small rocks in shallow waters and larger rocks in deeper areas of the lake. However, they are incredibly sensitive to temperature changes and will not survive in water below 25.5 degrees Celsius. Keeping these remarkable creatures in a home aquarium requires attention to detail and ensuring the aquarium's water temperature is maintained correctly. 


Breeding the Sulawesi Harlequin Shrimp in the home aquarium is achievable with the appropriate water conditions and nutrition. Unlike many other shrimp species, they do not have a larval stage. Instead, the female carries her reddish-coloured eggs between her swimmerets for around 20 to 28 days until they hatch as miniature replicas of the adults, displaying the same vibrant colouration but not as intense. The shrimplets have a rapid growth rate if the tank is well-maintained and provides a suitable habitat for them to thrive.

Diet & feeding

Maintaining a balanced diet for your Sulawesi Harlequin Shrimp is imperative to ensure their overall well-being. Although these shrimp are known to graze on algae constantly, supplementing their diet with algae wafers, shrimp pellets, or crushed flakes is crucial in providing a complete diet. It is also recommended to offer them meaty treats occasionally. Due to their small size, it is essential to provide them with appropriately sized food portions. In addition, it is advisable to feed them during the dark hours and avoid overfeeding, giving them only what they can consume within a period of two to three hours.

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