Harlequin Shrimp: A Colorful Guide to Aquarium Care

Harlequin shrimp, scientifically known as Hymenocera picta, are one-of-a-kind saltwater crustaceans that bring life and color to any aquarium. These vibrant creatures are found in coral reefs across the tropical Indian and Pacific Oceans, with regional color differences such as white bodies with maroon to purple spots or light blue spots. Not only are they a visual delight, but they also play a crucial role in maintaining coral health by preying on pests like Asterina starfish.

As you learn about these captivating invertebrates, you’ll discover their unique attributes and behavior. Their fascinating predatory habits not only make them attractive additions to your tank but also contribute to the wellbeing of your entire aquatic ecosystem.

In this article, you’ll find everything you need to know about Harlequin shrimp care, from tank size and ideal habitats to diet recommendations. So, without further ado, let’s get started on your journey to becoming an expert Harlequin shrimp caregiver.

Species Overview

Harlequin shrimp are a vibrantly colored saltwater species native to the Pacific and Indian Oceans. These shrimp are known for their monogamous and territorial nature, making them unique among shrimp species. They are also sought-after by aquarists for their beautiful appearance and interesting behaviors.

Harlequin shrimp are primarily carnivorous, feeding on starfish and occasionally sea urchins. They are relatively easy to care for, but their specific diet requirements should be kept in mind when considering them for your aquarium. They are sensitive to sudden environmental changes and require stable water conditions to thrive.

Here’s a table summarizing the key information about Harlequin shrimp:

Property Information
Scientific name Hymenocera picta
Common names Harlequin shrimp, Painted shrimp
Distribution Pacific and Indian Oceans
Size 1.5-2 inches (Females larger than males)
Lifespan About 7 years
Diet Carnivorous (starfish, sea urchins)
Temperament Monogamous, territorial
Minimum tank size 10 gallons, with ample hiding spaces
Temperature 72-84°F / 22.2-28.8°C
pH 8.0-8.4
Water Hardness Salinity: 1.023-1.025
Care Level Moderate
Filtration/Water Flow Standard aquarium filtration and water flow
Water Type Saltwater
Breeding Sexual reproduction (eggs produced in female)
Breeding Difficulty Moderate
Compatibility Compatible with other peaceful marine species

Follow the recommended guidelines in the table above for a successful Harlequin shrimp experience in your aquarium.

Harlequin Shrimp Basics

Origins and Natural Habitat

Harlequin shrimp, native to rubble piles outside coral reefs, are primarily found in the Indo-Pacific region and Hawaii. They inhabit the waters of the Pacific and Indian Oceans, where they can be seen in various color differences based on their location.

Size and Shape

The size of Harlequin shrimp varies, with females generally being larger than males. Average size of these shrimp ranges within two inches, making them suitable for saltwater aquariums. Their shape is quite unique, as they possess flat, leaf-like appendages and long antennae, which helps them stand out from other shrimp species.

Color and Markings

The colors and markings of Harlequin shrimp are truly spectacular, with their vibrant blue, purple, and maroon spots outlined on white bodies. The female shrimp have larger colored blotches in the ventral region of their abdominal segments, adding to their distinctive appearance. This striking combination of colors and patterns make them a favorite among aquarium hobbyists.


The average lifespan of a Harlequin shrimp is 3-5 years. However, with proper care, an optimal environment, and a balanced diet, these shrimp can thrive in captivity and live up to their full potential. Regular maintenance and monitoring of water conditions can further help in ensuring their longevity.

Harlequin shrimp are an exquisite addition to saltwater aquariums due to their unique appearance and vibrant coloration. By understanding their natural habitat, size, shape, and lifespan, you can better care for and appreciate these amazing creatures.

Diet and Feeding

As the caretaker of Harlequin Shrimp, you’ll need to know about their unique diet. These shrimp have a specialized natural diet that mostly consists of starfish and occasionally sea urchins. In particular, Harlequin Shrimp have a preference for the tube feet of starfish.

To provide a proper diet for your Harlequin Shrimp, ensure that you have a supply of starfish available in their tank or via regular feedings. Take note that some types of starfish might be toxic or too large for your shrimp, so it’s essential to choose appropriate species, such as Asterina or Linckia.

It’s crucial to observe your shrimp’s feeding habits carefully. Harlequin Shrimp are known to stand on starfish to immobilize them before consuming the tube feet. Monitoring their feeding will help you respond to their needs and maintain their overall health.

By understanding and catering to the Harlequin Shrimp’s distinct feeding requirements, you’ll create a thriving environment for these fascinating creatures.

Behavior and Temperament

Harlequin shrimp, scientifically known as Hymenocera picta, are generally peaceful creatures that thrive in coral reef environments in the Pacific and Indian Oceans. Despite their vibrant appearance, they are quite shy and tend to hide during the daytime. They become more active after dusk, hunting for their prey.

As a carnivorous species, Harlequin shrimp have a unique diet that mostly consists of starfish, which they eat by flipping them over and feeding on their tube feet and soft tissue. Due to their specialized diet, it is crucial to provide them with enough suitable food sources to maintain their health.

In terms of social behavior, Harlequin shrimp often form monogamous pairs. Once bonded, they cooperate by sharing the workload when hunting for food. This teamwork is a fascinating aspect of their behavior and is indeed a spectacle to watch in a well-maintained marine aquarium.

Care and Tank Requirements

Tank Size

To provide the best environment for your Harlequin Shrimp, you’ll want to start with a suitable tank size. These shrimp can grow up to 2 inches in size, so a tank with a capacity of at least 10 gallons is recommended. This will allow your shrimp to have plenty of space for moving, hiding, and feeding.

Water Parameters

Harlequin Shrimp are sensitive to water quality, so it’s crucial to maintain optimal conditions in their tank. The water temperature should be between 72-82°F, with a specific gravity of 1.023-1.025. Maintain a pH level between 8.1-8.4, and ensure that the ammonia, nitrite, and nitrate levels stay low. Regular water testing and water changes are vital for keeping your shrimp healthy.

Tank Setup and Decorations

Your Harlequin Shrimp will appreciate a tank with a variety of hiding spots and surfaces to explore. Use live rock, caves, and coral to create a natural environment that mimics their native habitat. Make sure to leave some open space for them to roam and search for food. Provide a sandy substrate to allow the shrimp to dig and burrow if they desire.

Filtration and Aeration

Implementing efficient filtration and aeration systems is important for maintaining water quality and providing oxygen for your shrimp. Choose a filter designed for saltwater environments that can handle the tank’s capacity. A protein skimmer can also be beneficial for removing waste and excess nutrients from the water. Use an air pump and air stone to provide additional oxygenation for your Harlequin Shrimp’s comfort and well-being.

Suitable Tank Mates

When selecting tank mates for your Harlequin Shrimp, it’s essential to consider both their size and temperament to ensure harmony in your aquarium. A few suitable options that generally work well with Harlequin Shrimp include:

  • Basslets
  • Cardinalfish
  • Clownfish
  • Firefish
  • Gobies (particularly Mandarin Gobies)
  • Lawnmower Blennies
  • Scarlet Cleaner Shrimp
  • Small Hermit Crabs
  • Snails
  • Tangs (such as Purple Tangs)

In addition, Blood Red Fire Shrimp (specifically the Cherry Shrimp variety) have been known to be compatible tank mates. You might also consider adding Clams and Feather Duster Worms as other compatible additions to a Harlequin Shrimp environment.

It’s important to remember that while these tank mates are generally suitable, individual shrimp may have specific preferences. As a result, you should always monitor interactions between your Harlequin Shrimp and its tank mates, making adjustments as needed to ensure a peaceful and thriving community in your aquarium.


Breeding Harlequin Shrimp can be an exciting process. When pairing these shrimp, opt for a mixed-sex pair, as they will breed more effectively and cooperate in hunting. To determine the sex of each shrimp, examine their undersides – males are spotless, while females have a spotted pattern.

Females reach sexual maturity around 200 to 240 days old and will begin to spawn after each subsequent molt, which typically occurs every 18 to 26 days. When females become pregnant, they carry fertilized eggs under their abdomens in a process called “berrying.” During this time, they use their tail to fan and oxygenate the eggs, which takes about two to three weeks.

Keep an eye on the eggs – once they turn translucent and the shrimp stop eating (usually two to three days before hatching), it’s best to relocate both parents to a separate tank with similar conditions. This helps reduce the shrimp’s stress levels during the final phase of the eggs’ development.

After around five to six weeks, the eggs hatch, and the shrimplets enter a planktonic phase. At this point, you can return the parents to their original tank. Meanwhile, the shrimplets will start crawling and feeding on green water algae and rotifers before transitioning to shrimp nauplii. Remember to maintain a friendly environment for your new little friends, and happy shrimp-keeping!

Common Diseases and Treatments

Though Harlequin Shrimp are not susceptible to specific diseases, it’s important to remember that they are highly sensitive to small changes in tank conditions. To ensure the health of your shrimp, you’ll need to be diligent in maintaining a stable and clean environment.

One of the essential aspects of tank maintenance is removing molted shells, dead fish, starfish carcasses, and other decomposing substances. This prevents the release of harmful ammonia or nitrates which could pose a threat to your shrimp.

Pay close attention to the copper content in any additions to the tank, as even tiny amounts of copper can be harmful to Harlequin Shrimp. Regularly checking the copper content will help to prevent any unintentional exposure.

Maintaining good water quality and cleanliness is crucial for your shrimp’s well-being. Make it a habit to monitor tank conditions consistently and ensure the water is free of harmful substances and pollutants. Regular water changes and proper filtration should be part of your routine.

By staying vigilant in monitoring and controlling the tank conditions, you can help prevent potential issues and keep your Harlequin Shrimp healthy and thriving. Remember, a happy shrimp makes for a happy you!

Frequently Asked Questions

How often to feed Harlequin Shrimp?

Harlequin shrimp are known to eat mostly starfish and you should ensure they have a steady supply of food. The frequency may vary depending on their consumption. Pay attention to your shrimp’s behavior and if you see them searching for food, it might be time to provide another starfish.

What do Harlequin shrimp eat?

Harlequin shrimp have a peculiar diet – they primarily consume starfish, specifically the Asterina starfish which infest home aquariums. Always make sure that they have an adequate supply of starfish to maintain their health and vitality.

Are Harlequin shrimps reef safe?

Yes, Harlequin shrimp are reef safe and considered a peaceful and shy species. They can coexist well with other compatible marine species in your aquarium while adding a stunning visual element as they are quite attractive creatures.

Which fish species can prey on them?

Harlequin shrimp are small and delicate, which makes them potentially vulnerable to various larger and aggressive fish species. Avoid housing them with fish such as lionfish, groupers, hawkfish, or any other predatory species that can view the shrimp as potential prey.

Do they consume all types of starfish?

Although they primarily consume Asterina starfish, Harlequin shrimp are known to eat other types of starfish as well. If your pet shrimp finishes eradicating a particular kind of starfish in your aquarium, you might want to supply them with a different variety to maintain their dietary needs.