Mantis Shrimp In Reef Tank – The Ultimate Guide To Keeping
For years, the thought of keeping a mantis shrimp in reef tank environments was enough to make any seasoned hobbyist shudder in fear. You’ve likely heard the horror stories: shattered glass, decimated clean-up crews, and fish disappearing into the night without a trace.
I completely understand if you feel a bit apprehensive about bringing one of these “thumb-splitters” into your home. However, I promise you that when kept correctly, these creatures are among the most intelligent, charismatic, and visually stunning inhabitants you can ever host.
In this comprehensive guide, we are going to debunk the myths and look at the practical reality of keeping these stomatopods. We’ll explore the best species for your setup, how to build a “shatter-proof” home, and how to enjoy their incredible behavior without losing your sanity (or your snails).
Understanding the Stomatopod: More Than Just a “Shrimp”
The first thing you need to know is that a mantis shrimp isn’t actually a shrimp at all. They are stomatopods, a distinct lineage of crustaceans that branched off from others hundreds of millions of years ago.
When you decide to keep a mantis shrimp in reef tank displays, you aren’t just adding an invertebrate; you are adding a predator with high-level cognitive function. These animals have some of the most complex eyes in the animal kingdom, capable of seeing polarized light and colors we can’t even imagine.
They will watch you through the glass, track your movements across the room, and even learn to recognize the “person with the food.” This level of interaction is rare in the saltwater hobby, making them more like “underwater dogs” than simple crustaceans.
Smashers vs. Spearers: Knowing the Difference
Before you buy, you must understand the two primary “hunting styles” of stomatopods. This choice will dictate your entire tank setup and what kind of biological load or tank mates you can consider.
Smashers possess heavily calcified clubs used to bludgeon prey like snails and crabs. These are the most common species kept in the hobby because they are often more colorful and slightly easier to house in smaller volumes.
Spearers, on the other hand, have barbed appendages designed to snatch fast-moving fish out of the water column. While fascinating, they usually require much deeper sand beds and are significantly more dangerous to any fish you might want to keep.
Designing the Perfect Setup for a Mantis Shrimp in Reef Tank
Creating a home for these animals requires a shift in mindset compared to a traditional reef. You aren’t just building a coral garden; you are building a fortress that meets the specific psychological needs of a highly territorial hunter.
To keep a mantis shrimp in reef tank systems healthy, you need to prioritize their burrowing behavior. Without a secure place to hide, a mantis shrimp will become chronically stressed, which can lead to failed molts and a shortened lifespan.
The Glass Breaking Myth: Reality Check
Let’s address the elephant in the room: will they break the glass? While it is physically possible for a large “Smasher” (like a full-grown Peacock Mantis) to crack thin glass, it is incredibly rare.
Most “glass-breaking” incidents occur when a mantis shrimp tries to burrow and hits the bottom pane, or when it sees its reflection and attacks it. To prevent this, I always recommend using thick tempered glass or, even better, an acrylic aquarium.
Acrylic is much more impact-resistant than glass. If you are using a glass tank, placing a thin sheet of acrylic or a piece of egg-crate (light diffuser) on the bottom before adding sand can protect the bottom pane from “accidental” strikes.
Substrate and “The PVC Trick”
A mantis shrimp’s life revolves around its burrow. In the wild, they spend a massive amount of time engineering their homes. In your reef tank, you should provide a mix of coarse sand, crushed coral, and rubble.
One of my favorite “pro tips” for new mantis keepers is to bury a U-shaped or L-shaped PVC pipe beneath the rockwork. Make sure the diameter is slightly larger than the shrimp.
By providing a pre-made “starter home,” you can often dictate where the shrimp lives, ensuring it chooses a spot where you can actually see it! This prevents them from disappearing into the deep crevices of your live rock for weeks at a time.
Choosing the Best Species for Your Tank
Not all stomatopods are created equal. Some grow to nearly a foot long, while others stay the size of a paperclip. Choosing the right species is the difference between a thriving display and a maintenance nightmare.
The Peacock Mantis (Odontodactylus scyllarus)
The “holy grail” for many is the Peacock Mantis Shrimp. They are breathtakingly beautiful, with iridescent greens, reds, and blues. However, they are also one of the largest smashers, requiring at least a 40-gallon tank.
Because of their size and power, they are the most likely candidates for glass breakage. If you choose a Peacock, ensure your filtration is over-sized, as they are messy eaters that produce a lot of waste.
The Wennerae (Neogonodactylus wennerae)
If you are a beginner, I highly recommend the N. wennerae. These are often found as “hitchhikers” in Florida live rock. They stay small (about 2-3 inches), are very hardy, and are much less likely to damage your aquarium.
They fit perfectly into a 10 or 20-gallon “nano” reef. Their colors can range from bright lime green to deep burgundy, depending on the lighting of your tank. They are the perfect “gateway” into the world of stomatopods.
The Smithii (Gonodactylus smithii)
Also known as the Purple Spot Mantis, these are legendary for being incredibly “personable.” They are active during the day (diurnal) and spend a lot of time peering out of their burrows. They are moderately sized and generally very hardy in a stable reef environment.
Water Parameters and Coral Compatibility
One of the best parts about keeping a mantis shrimp in reef tank setups is that they are generally “reef safe” when it comes to corals. They don’t eat polyps, and they don’t nip at stony corals.
However, they are habitat modifiers. If a frag is in their way or they think a piece of rubble would look better at the front of their door, they will move it. I suggest gluing your corals down securely with epoxy to prevent your shrimp from “redecorating” your expensive Acropora.
Filtration and Stability
Mantis shrimp are sensitive to high levels of nitrates and copper. Because they are crustaceans, any copper-based medication is lethal. You should aim for standard reef parameters:
- Salinity: 1.025 – 1.026
- Temperature: 76°F – 80°F
- Nitrates: < 10ppm (if possible)
- Iodine: This is crucial for successful molting.
Regular water changes are your best friend. Since mantis shrimp are messy eaters—leaving bits of crab shell and shrimp meat everywhere—a good protein skimmer is highly recommended to prevent nutrient spikes.
Diet, Feeding, and Enrichment
Feeding time is where the mantis shrimp in reef tank experience really shines. Watching a smasher take down a piece of food is a display of pure biological engineering.
You should provide a varied diet to ensure they get the nutrients needed for their complex shells. Frozen krill, silversides, clams, and squid are excellent staples. I recommend using long feeding tongs to deliver food—never use your fingers!
The Importance of “Work”
In the wild, these animals spend their days hunting. If you only feed them soft, frozen food, their “clubs” can actually begin to atrophy or become damaged over several molts.
To keep them healthy, you must provide live “work” occasionally. Drop in a few “feeder” snails (like Astrea or Nerite snails) or small blue-leg hermit crabs once a week. This allows the shrimp to use its striking mechanism, which is vital for its physical and mental well-being.
Tank Mates: What Can Survive?
This is the most common question I get: “Can I keep fish with my mantis shrimp?” The answer is a cautious “maybe,” but it depends entirely on the species of shrimp and the fish.
If you have a Smasher, fast-moving, top-dwelling fish like Damsels or Chromis often do just fine. The shrimp is looking for slow-moving, bottom-dwelling prey with shells. However, any fish that tries to enter the shrimp’s burrow will likely be killed instantly.
If you have a Spearer, you should generally keep them in a species-only tank. They are evolved specifically to catch fish, and they are frighteningly efficient at it.
Avoid:
- Bottom dwellers (Blennies, Gobies)
- Expensive decorative shrimp (Skunk Cleaners, Fire Shrimp)
- Valuable snails or crabs you aren’t prepared to lose
The Molting Process: A Critical Time
Every few months, your mantis shrimp will undergo a molt. This is the most dangerous time in their lives. You will know it’s coming because they will often seal themselves inside their burrow with rocks and sand for several days.
Do not attempt to dig them out! Even if you haven’t seen them for a week, stay patient. During this time, their new shell is soft, and they are incredibly vulnerable. Any stress or physical interference can be fatal.
Ensure your Iodine levels are stable, as this helps the crustacean separate the old shell from the new one. Once they emerge, they will often be more colorful and have a voracious appetite!
FAQ: Common Questions About Mantis Shrimp
1. Can a mantis shrimp really break a human finger?
While “thumb-splitter” is a common nickname, a strike from a medium-sized mantis shrimp is more likely to cause a deep laceration and a possible bone bruise rather than a clean break. However, it is extremely painful. Always use tongs.
2. How long do they live in captivity?
With proper care, smaller species live about 3-5 years, while the larger Peacock Mantis can live for 7-10 years or even longer in some cases.
3. Do they need special lighting?
Mantis shrimp don’t need special light, but too much light can actually be harmful to some species. Deep-water species can develop “shell disease” (a type of rust-colored algae growth on the shell) if exposed to intense reef lighting. Provide plenty of shaded areas.
4. Can I keep two mantis shrimp together?
Unless you have a massive tank and a known mated pair, absolutely not. They are highly territorial and will fight to the death. One mantis per tank is the golden rule.
5. Why is my mantis shrimp changing color?
Stomatopods can change color slightly after a molt to better blend in with their environment. If you have a lot of green macroalgae, a brown shrimp might emerge from its molt with a greenish tint!
Conclusion: Is a Mantis Shrimp Right for You?
Keeping a mantis shrimp in reef tank systems is one of the most rewarding challenges in the aquarium hobby. It moves away from the “look but don’t touch” nature of many reef tanks and enters the realm of keeping a truly sentient, interactive pet.
Yes, you have to sacrifice your snails. Yes, you need to be careful with your fingers. But in exchange, you get to witness one of nature’s most incredible predators in action. You’ll find yourself spending hours watching them “engineer” their burrows and interacting with you through the glass.
If you are tired of the standard “fish and coral” formula and want an animal with real personality, the mantis shrimp is waiting for you. Just remember: respect the power of the strike, provide a secure burrow, and enjoy the show! Happy Reefing!
