Mantis shrimp aren’t your typical reef tank residents, but they sure pack a punchโliterally!
These feisty critters are not reef-safe and require careful handling. Known as “thumb splitters” for a reason, they can easily damage tank mates or even aquarium glass if not properly managed.
This guide will provide essential insights into maintaining a tank for your mantis shrimp while highlighting the challenges you may face.
Quick Facts
- Common Names: Mantis Shrimp, Stomatopod, Thumb Splitter
- Care Difficulty: Moderate to Difficult
- Role: Predator
- Diet: Carnivorous
- Temperament: Aggressive
- Reef Compatibility: Not reef-safe
- Minimum Tank Size: 30-90 gallons
- Size: 4-12 inches
- Lifespan: 3-6 years
- Reproduction: Very rare
- Native Region: Tropical and subtropical waters worldwide
- Varieties/Types: Peacock mantis shrimp, zebra mantis shrimp

What Mantis Shrimp Look Like
Think of mantis shrimp as the peacocks of marine life, at least the ones often sold for reef tanks. They have a kaleidoscope of colors, often seen in shades of green, blue, red, and orange.

Their body is mostly hard-shelled except for the rear part of their head and the first four thoracic segments. This partial armor gives them a rather segmented look.
Their eyes are large and perched on mobile stalks that move independently. It’s like they have a built-in periscope! But these eyes are not just for show. They’re complex and essential for their hunting ability.

Depending on the species, they might be “spearers” with sharp spines or “smashers” with club-like limbs. Either way, these tools make quick work of their prey. And sometimes, your glass tank.
Looking at similar creatures, you might confuse them with:
- True Shrimp: They have smaller eyes and longer antennae, lacking the mantis shrimp’s big eyes and distinct front limbs.
- Crayfish or Small Lobsters: They have larger front claws and a more uniform body shape, unlike the mantis shrimp’s specialized appendages and uprighting segmented body.
- Pistol Shrimp: They have a big snapping claw instead of the mantis shrimp’s predatory appendages for striking prey.
Diet and Feeding
When looking at feeding a mantis shrimp, you’re dealing with a real predator. These guys hunters through and through.

In the wild, mantis shrimp have a carnivorous diet that includes crustaceans, mollusks, and fish. They’re divided into two groups based on their hunting style: “smashers” and “spearers.”
- Smashers love hard-shelled prey like crabs and snails.
- Spearers go for soft-bodied targets like fish.
But be warned. They will eat invertebrates or fish if given the chance. So, they’re definitely not reef-safe!

Feed your mantis shrimp every other day or 2-3 times per week. This keeps them active and healthy without overfeeding.
In terms of sourcing food for your mantis shrimp, you’ve got options. Live prey can be exciting for them to hunt down, but they may accept frozen foods like shrimp, squid, or fish, which are also good choices. Just make sure there’s no added iodine or preservatives.
Cost-wise, feeding a mantis shrimp is fairly reasonable. You might spend around $10-20 monthly on food, depending on whether you choose live prey or frozen options from the store.
One thing I’ve noticed about these creatures is their intelligence when it comes to feeding time. They seem to recognize when it’s time for a meal and can become quite active as soon as you approach the tank with food in hand.
However, always be cautious when placing food in the tank because you don’t want to accidentally become their next victim.
Tank Setup
You’ll want to start with a tank that’s at least 30 gallons, though bigger is better, especially if you’re housing larger species like the Peacock Mantis Shrimp.
These crustaceans are solitary creatures, so keeping just one per tank is best. Their territorial nature means they’ll fiercely defend their space, making it risky to house them with other inhabitants.
For substrate, think of deep sand beds with mixed grain sizes. This provides the perfect playground for burrowing, which these shrimp love to do. Stable rockwork is very important because their burrows may unsettle things in your tank.

Lighting should be low to moderate. Too much light can lead to shell rot, which is something we definitely want to avoid. If you’re keeping SPS corals in a somewhat shallow tank, it’s best to avoid getting a mantis shrimp.
Water quality is important, as is the case with any shrimp species. Keep your ammonia and nitrite levels at 0 and nitrates below 10 ppm. Maintaining calcium levels between 400-450 ppm and magnesium between 1300-1400 ppm ensures healthy exoskeleton development.
If you’re new to acclimating mantis shrimp or unsure about maintaining stable water parameters, I recommend checking out my detailed acclimation guide.
Behavior and Tank Mates
Mantis shrimp have a reputation for their aggressive temperament. They’re highly territorial, fiercely defending their space against intruders. This makes them mostly solitary in the tank.
Depending on which species you have, you’ll notice mantis shrimp being most active during the day if they’re diurnal or at night if they’re nocturnal.
They spend much of their time in or near their burrows, only emerging to hunt or relocate. Their hunting style is quite something. Quick and powerful strikes that leave prey little chance to escape.
Mantis shrimp should ideally be kept alone due to their predatory nature. Good tank mates are non-existent because they might attack fish or other invertebrates if given the opportunity.
Avoid friendly species like cleaner shrimp, peppermint shrimp, and coral-banded shrimp, as these can easily become targets.
One common question is about the impact of mantis shrimp on corals. While they aren’t particularly interested in corals, some large colony corals might get damaged by smasher species during hunting activities.
Regular molting is important for them to maintain health and strength, as it enables them to repair damaged tissues and regenerate lost limbs.
As for molting frequency, mantis shrimp typically molt every few weeks when they’re young, allowing them to grow quickly and strengthen their exoskeletons. As they reach adulthood, the molting intervals extend, and they might molt every few months instead.
Breeding and Reproduction
Breeding mantis shrimp in a home reef tank is quite rare and challenging. It’s not something most reef keepers will experience with mantis shrimp in captivity.
Most individuals sold are wild-caught specimens rather than captive-bred ones.
However, if you do see any courtship behaviors like males displaying bright colors or performing dances, consider yourself lucky!
For home reef keepers interested in this aspect, providing enough space for potential courtship displays and maintaining excellent water quality might help, but there are no guarantees.
Common Health Issues
Symptoms to Watch For:
- Shell Disease: Look for discoloration or lesions on their exoskeleton.
- Molting Problems: Difficulty shedding or incomplete molts.
- Behavioral Changes: Increased hiding or lethargy.
- Feeding Habits: Decrease in appetite or refusal to eat.
Treatment Options:
- Shell Disease: Improve water quality and make sure of stable parameters.
- Molting Issues: Check iodine levels (between 0.04 to 0.06 ppm).
- General Stress: Provide enough hiding spots and reduce tank stressors.
Regular testing for ammonia, nitrite, and nitrate levels is important. Make sure calcium and magnesium are at optimal levels for exoskeleton development. And keep in mind, avoid copper products like the plague because mantis shrimp are super sensitive to them, and it will kill them!
Can You Keep Mantis Shrimp in a Reef Jar?
No.
Mantis shrimp need tons of space, and reef jars can’t provide that. Their aggressive nature means they’re not suited for such small environments where they will feel cramped or stressed.
And since they aren’t reef-safe, they’d likely wreak havoc on any other inhabitants you’d have in a tiny setup like a reef jar.