Sexy shrimp

Invertebrates · Care guide

Sexy Shrimp Care: Thor amboinensis

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Direct answer: Sexy shrimp (Thor amboinensis) are a captivating addition to any saltwater aquarium, known for their vibrant colors and unique “dancing” behavior. They are reef-safe and ideal for nano or pico tanks. However, they may nibble on coral polyps and may get eaten by protein-forward predators already in your tank.

The sexy shrimp (Thor amboinensis) checks every box when it comes to invertebrates. Intriguing name? No need to explain that one. Engaging behavior? They’ll happily distract you from every task on your To-Do List. Fascinating to look at? Well, they’re not called “sexy shrimp” for nothing! If you haven’t already found yourself looking to add these adorable crustaceans to your aquarium, what are you waiting for?

Table of Contents: Sexy Shrimp Care

Use the links below to navigate directly to the section that interests you, or read on for a comprehensive guide to sexy shrimp care.

Quick Facts

  • Common Names: Sexy shrimp, Anemone shrimp, Dancing shrimp, High-tailed shrimp, Pikmin shrimp, Squat shrimp, Sexy cleaner shrimp, Squat anemone shrimp, Ambon shrimp
  • Scientific Names: Thor amboinensis
  • Size: Up to 1¼ inches (3.2cm)
  • Minimum Tank Size: 5 Gallons (19L)
  • Reef Safe? Yes
  • Care or Experience Level: Easy
  • Preferred Diet: Omnivore
  • Original Part of the World: Circumtropical
Sexy shrimp have distinct orange and white patterns

Description of the Sexy Shrimp

Unlike other shrimp, sexies sport upturned abdomens and tails that curl back towards their heads. This leaves their legs free for dancing – a behavior they’re FAMOUS for. It’s also where the “sexy” part of the name comes in. With legs on constant display, they serve as the divas of the crustacean world. (Really, though, with “Thor” in their scientific name, could you expect anything less?)

However, plenty of people overlook these cuties. Sexy shrimp don’t grow much beyond 1¼ inches (3.2cm). Even with a vivid color palette, that allows them to slide under the radar. And since they develop commensulate relationships with sea anemones, it makes them harder to spot out on the reef. Hiding out within the protection of stinging tentacles, sexies clean the anemones. It’s an excellent symbiotic partnership. Of course, some sexy shrimp decide to nip at the anemone’s protective mucus – or even the ends of the tentacles. But when you’re THAT bitty? A few nibbles here and there won’t cause significant damage.

Sexies aren’t picky about the anemone they pair up with. Scientists and divers have spotted them climbing in, on, and around all of the following:

  • Actinodendron plumosum
  • Anemonia sulcata
  • Cryptodendrum adhaesivum
  • Entacmaea quadricolor
  • Heteractis spp.
  • Lebrunia danae
  • Macrodactyla doreensis
  • Phymanthus spp.
  • Stichodactyla spp.
  • Telmatactis cricoides
  • Zoanthus spp.

Sexy Shrimp Lifespan

Sexy shrimp circle the globe in the tropical regions. As long as they have a suitable sea anemone to partner with, they’re happy. Of course, divers and snorkelers need a keen eye to spot them among the tentacles of that anemone – even with those 3-D spots. The groups of shrimp don’t stand out the way you’d think. Well, not to humans, anyway.

To other invertebrates and fish, though, they’re hard to miss. Good thing sexies are one of the fastest crustaceans around. They can “sprint” for short distances at an impressive speed of 4-6 inches/second (10-15cm/second). That’s assuming a predator isn’t deterred by their dancing, of course. (We’ll cover that in a minute)

Combine that speed and a natural camouflage (not to mention the protection of the sea anemone’s sting), and sexy shrimp survive for around 3-5 years in the wild. In a captive environment, the average comes out closer to three years. This is usually due to management issues. But if you’re tops in your care, you may see longer.

Sexy shrimp share symbiotic relationships with sea anemones

Creating the Ideal Sexy Shrimp World

If you’re in a tropical reef, your odds of spotting sexy shrimp go up. Their preferred host anemones pop up in those warm waters. Officially, there’s ONE species of sexy shrimp out there. But a study in 2018 looking at genetic markers suggested five geographic lineages for sexies: western Atlantic, Red Sea, western Pacific, Japan, and Polynesia. Currently, though, no one’s decided to “break up the set” into subspecies.

Sexies are happy in water depths between 6-80 feet (2-25m). Of course that depth is irrelevant in the aquarium world, but the key takeaway is they’re used to it being sunny.

They form groups that cluster around their chosen anemone during the day. They’ll stay “close to home” while the sun’s out, sometimes venturing as close as the oral disk in their cleaning duties. Once the sun goes down (and the anemone retracts those stinging tentacles), sexies move away to another hiding place.

Despite what you’re probably thinking, you DON’T need to add a sea anemone to your tank if you want to keep sexy shrimp. While they appreciate it, these invertebrates adapt to their surroundings. And that means these reef safe shrimp happily accepting alternatives of live rock and coral. Hiding places – such as the natural caves and crevices of a live rock structure – are the key.

Understanding the Role of Anemones in Sexy Shrimp Care:

In the wild, sexy shrimp form symbiotic relationships with sea anemones. The anemone provides protection from predators with its stinging tentacles, while the shrimp help keep the anemone clean by feeding on debris and sometimes its mucus. This partnership also offers the shrimp access to food scraps and a secure base for social interactions.

When kept without anemones in captivity, sexy shrimp will adapt by seeking shelter among live rock or corals. However, the absence of their natural host can lead to several changes:

  • Behavioral shifts: Shrimp may become more reclusive, spending more time hiding, especially if they feel exposed or threatened. Some may show increased stress or even mild aggression toward each other if shelter is limited.
  • Increased predation risk: Without the protective tentacles of an anemone, shrimp are more vulnerable to predatory tank mates. They rely more heavily on available rockwork and crevices for safety.
  • Potential for coral grazing: In the absence of anemones, shrimp may interact more with corals, sometimes grazing on polyps or mucus—especially if underfed or stressed.

To mitigate these risks, provide dense rockwork with multiple caves, overhangs, and crevices. Artificial anemone substitutes or soft coral analogs can also offer additional shelter. Monitor your shrimp for signs of stress (such as constant hiding or reduced activity) and ensure they are not being harassed by tank mates. If you notice abnormal behavior or increased coral grazing, reassess tank layout, feeding practices, and compatibility.

While sexy shrimp can thrive without anemones, understanding these trade-offs will help you create a more secure and naturalistic environment, supporting their health and reducing risk to both shrimp and corals.

Sexy shrimp remain active AND visible during the day. It’s one of the reasons aquarists love them so much. But they need somewhere to retreat to in the evening hours. Those adorable little crustacean bodies are hard for some fish to resist. And when you’ve danced the day away? You need somewhere safe to recover at night. If you don’t want the hassle of managing sea anemones, go for interesting contours of rock your sexies can explore.

Sexy Shrimp Tank Size

Given that precious minuscule size, sexy shrimp are a species ideal for pico or nano tanks. You can easily keep a group of 3-5 in a 5-gallon (19L) tank. (Incidentally, you WANT to keep a group. We’ll address why in a second) Of course, the smaller your tank, the more difficult the task of managing your water quality. So there’s a bit of a trade-off there.

See what fish are appropriate for 10-gallon, 20-gallon and 30-gallon reef tanks.

Are Sexy Shrimp Reef-Safe?

Sexy shrimp pair off with sea anemones. And while the odd shrimp may decide to take a nibble at a tentacle on occasion, they can’t do much damage. Even a group’s grazing won’t cripple the anemone. And you’d assume the same would apply if you placed your sexies into your reef tank, right?

In theory. Sexies don’t have a problem switching hosts to corals. The polyps of Duncan’s coral, green stars, clove corals, and mushrooms work as a nice compromise. And the colonies don’t seem to mind the presence of dancing shrimp. The problem arises when your sexy shrimp don’t receive enough proper food in their diet.

When hungry, sexies fall back on their tentacle-chewing habit. The corals then retract their polyps in defense. This leads to a reduction in photosynthesis by the zooxanthellae. And (in extreme cases), the coral may begin to die. As long as you DON’T allow your sexy shrimp to scavenge for food on their own, though, this shouldn’t turn into a problem–at least not a BIG problem.

If not fed properly, sexy shrimp may graze on coral polyps

Sexy Shrimp Diet

As sexy shrimp feed on the mucus of sea anemones (and the occasional tentacle nibble), some people consider them cleaner shrimp. However, while they are omnivores, they are NOT cleaner shrimp. You can’t expect them to scavenge your tank and survive. That’s what leads to sexies predating on corals.

Understanding Sexy Shrimp Nutrition and Feeding Practices:

Sexy shrimp are small, highly active omnivores with fast metabolisms. In the wild, they feed frequently on a mix of detritus, mucus, and small meaty items. In captivity, they require regular, small feedings to meet their energy needs and prevent opportunistic grazing on corals or tank mates. Insufficient protein or micronutrients—especially in tanks with little natural food—can trigger coral grazing and increased aggression.

For best results, feed your sexy shrimp a varied diet that includes:

  • Commercial sinking pellets or granules (formulated for marine invertebrates)
  • Meaty foods such as shredded clam or mysis shrimp
  • Algae-based foods (such as nori or spirulina flakes)

Feed small amounts once or twice daily, ensuring all shrimp in the group have access to food. In group settings, target feeding with a pipette or turkey baster can help distribute food and prevent dominant individuals or faster tank mates from monopolizing it. Rotate food types to provide a full spectrum of nutrients and avoid monotony.

Signs of underfeeding or malnutrition include increased hiding, lethargy, aggression, or visible coral grazing. If you observe these behaviors, increase feeding frequency or variety and monitor for improvement.

Be mindful that overfeeding—especially in nano or pico tanks—can quickly degrade water quality. Remove uneaten food promptly, and adjust your water change schedule or filtration (such as your protein skimmer) as needed to maintain stable parameters. Striking the right balance between adequate nutrition and water quality is key to long-term shrimp and coral health.

When you’re ready to stimulate breeding? Choose food items with higher fat contents. Prepare for the excess waste in your tank, though. You’ll want to step up your water changes or increase the setting on your protein skimmer.

Sexy Shrimp Behavior and Tank Mates

Where’d that “sexy shrimp” name come from? If you spot a group of these crustaceans together, you’ll understand. To communicate (as a warning of an approaching threat or an attempt to dissuade a predator), sexies wave that up-curved hind end in the air as if they just don’t care. And the more sexies in a group? The more often they dance.

Plenty of crustaceans prefer a solo existence. But sexy shrimp find low numbers stressful. “The more, the merrier” applies to this species. You don’t want to go below three for a group, or your sexies will attempt to hide out. It’s the group dynamic that eases that stress level and promotes activity.

Compatibility and Tank Dynamics:

Sexy shrimp are small, lack defensive weaponry, and display conspicuous movements—traits that make them vulnerable to predation by many fish species. Fish with large mouths, predatory instincts, or overlapping territory (such as clownfish, wrasses, and hawkfish) are especially risky. Even peaceful fish may opportunistically consume shrimp if the opportunity arises.

Group size matters: keeping sexies in groups of three or more reduces stress and encourages natural behaviors, but if space or shelter is limited, competition for hiding spots may increase. Always provide enough crevices and line-of-sight breaks to allow subordinate shrimp to escape aggression.

Introduction order is important. Adding sexy shrimp before more territorial or predatory species allows them to establish territory and find shelter. If added after, they may be harassed or eaten before acclimating.

Tank layout can mitigate risks. Dense rockwork, multiple shelters, and visual barriers help shrimp avoid aggressive tank mates and reduce predation risk. When evaluating new tank mates, consider:

  • Relative mouth size (can the fish eat a shrimp?)
  • Feeding habits (does the fish hunt invertebrates?)
  • Territorial overlap (do they compete for the same space?)

If in doubt, observe initial interactions closely and be prepared to rehome incompatible species. A simple rule: if a fish is known to eat shrimp or has a mouth large enough to do so, it is not a safe tank mate for sexy shrimp.

And while these delightful little dancers attract attention, it doesn’t mean you’re limited to that pico tank on your office desk. If you introduce sexies to the tank FIRST, you can set up a nano display with other species that will get along in perfect harmony:

Obviously, though, most fish find sexy shrimp a delightful snack. And clownfish top that list. Since the two share a preference for using sea anemones as hosts, they’re bound to come into conflict with each other. Well, perhaps “conflict” isn’t the right word. Your clownfish will happily devour your sexies, and thank you for delivering snacks.

Other fish you’ll need to avoid include:

Sexy shrimp earn their name from their dancing behavior

Breeding Sexy Shrimp

The majority of sexy shrimp come wild-caught. Since the species IS global in distribution (and not difficult to find), people haven’t rushed to set up captive breeding operations. Not to mention that breeding this particular crustacean is labor-intensive. It doesn’t mean you should write it off, but make sure you’re ready for the effort involved.

Sexy shrimp are protandric hermaphrodites. This means all shrimp are born male and switch to female when they reach an appropriate size (and with the right social cues). As such, females are the larger – and wider – of the two. The extra width allows them to carry the eggs. You’ll also see a “broken stripe” along the back and tail.

If you want to breed sexies, you’ll need a separate tank to raise the larvae. Without it, the more the tiny sexy shrimp end up eaten. (Yes, even if you have a single species tank) If you have the resources, a cylindrical recirculating tank works best. The shape allows the current to direct larvae AWAY from the glass walls. (They’re not strong enough to pull themselves away, and then you get squished shrimp which aren’t very sexy)

You’ll want the same water conditions but leave out all of the rock and substrate. All you need is a heater and an air stone (and don’t go overboard on the setting; all you want is gentle water movement).

Sexy shrimp lay anywhere between 100-300 eggs at a time. And you can encourage spawning with those high-fat foods. Eggs hatch within 2-3 weeks, usually in the evening. You’ll know it’s close to time because they’ll turn a dark brown color. To collect the larvae (and prevent them from becoming delicious snacks), add a light to one side of the tank. They’ll move toward it, allowing you to GENTLY siphon them up and transfer them into the rearing setup.

You don’t want more than 40 larvae per 2.5 gallons (10L). Any more, and you’ll end up with too much waste to cope with. Considering you need to perform 30-50% water changes TWICE a day as it is, cleanliness tops the list of importance.

The larvae should get around 14-16 hours of light a day, and you want to feed them freshly-hatched brine shrimp. That’s key as they only eat the yolk sac, which nauplii absorb in the first 12 hours.

Sexy shrimp undergo eight larval stages before they molt into a final decapod and settle. The development takes 26-28 days, with another 10-12 days before they emerge as their sexy selves. It means plenty of work for you. And it’s why no one’s embarking on commercial breeding operations. Not when collecting adults requires less time and effort.

Why Breeding Sexy Shrimp Is Challenging:

Breeding sexy shrimp in captivity is difficult for several biological and operational reasons:

  • Planktonic larval stage: Larvae are tiny, free-swimming, and highly sensitive to water quality and flow. They can easily get trapped on tank surfaces or sucked into filtration.
  • Feeding requirements: Larvae require live, appropriately sized food (such as newly hatched brine shrimp with yolk sacs) multiple times daily. Missed feedings quickly lead to starvation.
  • Water fouling: High feeding rates and larval waste rapidly degrade water quality, necessitating large, frequent water changes (30-50% twice daily).
  • Cannibalism and mortality: Overcrowding or poor water quality increases mortality and cannibalism among larvae.

Common failure points include larvae getting trapped on glass or in equipment, insufficient or mistimed feedings, and inability to maintain water quality. If you cannot commit to the demanding water change and feeding schedule, success is unlikely.

Most hobbyists rely on wild-caught sexy shrimp due to these challenges. However, supporting captive-bred individuals (when available) can help reduce pressure on wild populations and promote more sustainable aquarium practices.

sexy shrimp and hammer coral

Pros and Cons

Once you see a sexy shrimp group go into a dance, they’re hard to resist. And since they’re not difficult to care for, you’re probably planning your next nano or pico tank in your head. But every species comes with little quirks, and it’s important to look at every aspect before you make that purchase.

Pros

  • Unlike some crustaceans, sexy shrimp prefer to stick in groups – and the larger the numbers, the lower the stress level.
  • While sexies share a symbiotic relationship with sea anemones in the wild, you don’t need to keep an anemone in the tank; they’ll adapt to live rock or coral without a problem.
  • Sexy shrimp don’t require specialized diets, accepting anything from commercial sinking pellets to nori to meaty proteins.

Cons

  • While hardy, sexy shrimp don’t tolerate changes in water conditions, making it difficult to acclimate them when first bringing the invertebrates home.
  • If not fed well or adequately, sexies CAN start to graze on coral polyps.
  • Sexy shrimp will breed in captivity, but raising the fry is labor-intensive and complicated, making it easier to collect them from the wild.

For More Information

Finding a species of shrimp that’s active and visible during the day isn’t an easy task. It’s one reason hobbyists LOVE sexy shrimp. And if that isn’t enough for you (or, you know, getting to see how many times you can say “sexy” in one conversation before someone wonders what you’re talking about), you can always find some extra tidbits of information here.

Want to know about some of the best sexy shrimp tank mates?

Or maybe you’re interested in learning about the corals you can use as substitutes for anemones:

Stocking Strategies and Sample Plans

When planning your saltwater aquarium, consider tank size, compatibility, and the specific needs of each species. For sexy shrimp, smaller tanks (nano or pico) are ideal, and they thrive in groups. Always introduce the least aggressive species first—such as sexy shrimp—so they can establish territory before adding more territorial or predatory tank mates. This approach helps maintain a peaceful hierarchy and reduces stress.

Here are some sample stocking plans for different tank sizes:

5-Gallon Tank

  • 3-5 Sexy Shrimp
  • 1-2 Bumblebee Snails
  • 1 Clown Goby

10-Gallon Tank

  • 5 Sexy Shrimp
  • 2-3 Cerith Snails
  • 1 Neon Goby
  • 1 Peppermint Shrimp

20-Gallon Tank

  • 5-7 Sexy Shrimp
  • 3-4 Nassarius Snails
  • 1-2 Clown Gobies
  • 1 Skunk Cleaner Shrimp
  • 1 Emerald Crab

Common mistakes

Common mistakes when keeping sexy shrimp include failing to provide adequate hiding spaces, not feeding them properly, and introducing incompatible tank mates. Understanding the causes and consequences of these errors can help you avoid them:

  • Insufficient hiding spaces: Without enough crevices or caves, shrimp experience chronic stress, leading to hiding, reduced activity, and increased mortality. Early warning: Shrimp are rarely seen during the day or cluster in exposed corners.
  • Poor feeding practices: Infrequent or unvaried feeding can result in shrimp grazing on corals, lethargy, or aggression. Early warning: Corals retracting, shrimp picking at polyps, or visible weight loss.
  • Incompatible tank mates: Adding predatory or aggressive fish can lead to shrimp being eaten or harassed. Early warning: Unexplained shrimp disappearances or visible injuries.

Recovery steps: Add more shelter (rockwork, artificial caves), adjust feeding frequency and variety, or rehome incompatible species as needed. Regularly assess your tank using this checklist:

  • Are shrimp active and visible during the day?
  • Are all shrimp receiving food at each feeding?
  • Are corals healthy and fully extended?
  • Are tank mates peaceful and non-predatory?

Addressing issues early will improve long-term shrimp survival and tank harmony.

Final recommendation

Sexy shrimp are a delightful addition to any saltwater aquarium, especially for those with smaller tanks. Their vibrant colors and engaging behavior make them a favorite among hobbyists. Just be sure to provide the right environment and companions to keep them healthy and happy. With proper care, they can thrive and bring joy to your aquatic setup.

References

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