That Fish Blog – Aquarium Advice and Information

 

Like their fellow hitchhiker-turned-aquarium-stars, the Mantis Shrimp, Pistol Shrimp are coming into their own as popular aquarium additions. Unlike the Mantis Shrimp, most Pistol Shrimp can actually be kept with other tankmates.  They may even form bonds with some tankmates like Shrimpgobies that can be fascinating and entertaining to watch. Here are a few species of popular Pistol Shrimp for home aquariums.

Pistol shrimp get their name from the loud popping sound they can make by quickly opening or closing their specially adapted claws. This is used as a defense mechanism to frighten off would-be predators and, unlike the Mantis Shrimp they are sometimes confused with, they are harmless to most tankmates. They can be kept with most fish that will not prey on them but should not be kept with some other crustaceans, especially small shrimp or lobsters.

Tiger Pistol Shrimp (Alpheus bellulus)

The Tiger Pistol Shrimp is one of the most common and most popular pistol shrimp. It’s one of the species we get in to our store most often. These shrimp aren’t as striped as one would expect from a “Tiger” Pistol Shrimp but has a mottled, vaguely striped coloration in shades of tan, cream and reddish brown. The legs are striped and its claws have dark bands like the rubber bands on the claws of a lobster at a seafood restaurant. These pistols are true commensal species and may bond with any shrimpgobies – genus Cryptocentrus, Amblyeleotris, Stonogobiops and others. This species can grow up to about three inches in length and is one of the larger pistols.

 

Randall’s Pistol Shrimp (Alpheus randalli)

The Randall’s Pistol Shrimp is also known as the “Candy Cane” or “Red-banded Pistol Shrimp” and is one of the other species that we get in most often. While the Tiger Pistol Shrimp has a more mottled pattern, the Randall’s Pistol has more solid bright red and white stripes over a somewhat translucent body. The body and legs may be yellow – sometimes bright yellow – in some shrimp. This pistol shrimp only grows to about an inch and a half in length but, like the Tiger Pistol, isn’t too picky about which shrimpgoby it forms a pair with. It is better for smaller nano-reefs than the Tiger Pistol Shrimp.

 

Red Caribbean Pistol Shrimp (Alpheus sp.)

These pistol shrimp aren’t usually identified down to the exact species since several different species are almost identical. All are red with white markings, some with purple accents or banded antennas. However, these shrimp don’t usually pair with shrimpgobies. Instead, they form a relationship with the Curlycue Anemone (Bartholomea annulata), a common Caribbean anemone with long spiraling tentacles.

 

 

 

Green Pistol Shrimp (Alpheus euphrosyne)

The Green Pistol Shrimp is one of the more understated species. These shrimp have a brownish, olive green color more suited to the environment where they live. Rather than the rocky coral reefs of many others, the Green Pistol is found in muddy estuaries at the mouths of rivers, usually in full saltwater but some can tolerate the more brackish waters closer to the bays and mouths of the rivers. These shrimp are best kept in tanks with deeper, finer substrate closer to the muddy bottoms they have come from.

 

 

Pocillopora Pistol Shrimp (Alpheus lottini)

Pocillopora Pistol Shrimp are fascinating and rare pistols with a different modus operandi than other pistols. Like its common name suggests, these shrimp live within Pocillopora colonies. They will sometimes live alongside other coral-dwellers like Trapezia crabs where they may even work together to fend off attacks from coral-eating starfish like Cushion Stars or Crown Of Thorn Stars. They stay fairly small, usually well under two inches, and can vary in color. Most are yellow-orange with purple markings like speckles or a stripe down their back. Some of these may be regional variations, others may be subspecies.

Bullseye Pistol Shrimp (Alpheus soror)

The Bullseye Pistol Shrimp is one of the most stunning in appearance. The body is bright yellow-orange and the claws, legs and antennae are bright purple. Although they are also sometimes known as “Michael’s Pistol Shrimp”, the name Bullseye Pistol Shrimp comes from the white-ringed black spot on the middle of each side. This pistol shrimp is another that doesn’t usually form a bond with shrimpgobies. Some may share a burrow with some shrimpgobies, but they aren’t as reliant on the bond as other pistol shrimp and will often live on their own without a goby and may leave a pair at any time. This species also tends to be more active and will venture further from home and more into the open than others.

 

 

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These species are just some of the more common to enter the aquarium hobby. Others are sometimes available as well and each have their own unique behaviors and appearances but all can make for fascinating additions to a saltwater aquarium!

Skyrocketing in popularity over the past few years, Mantis Shrimp have gone from nuisance invaders to a specialty aquarium niche all their own (and a new superstar among viral animal posts thanks to comedic websites like The Oatmeal and zefrank’s YouTube videos). By far, the most popular of these crustaceans is the Peacock Mantis Shrimp, Odontodactylus scyllarus, but there are many other species that are just as fascinating and deserving of attention. We’ve featured mantis shrimp in general in several previous blogs; in this entry, we’ll investigate some of those other mantis shrimp that you may not hear about or see as much in media.

Smith’s Mantis Shrimp, Gonodactylus smithii
Its name may not be too familiar, but this mantis is one of the most photographed species due to its trademark meral spot. As you may remember your mantis shrimp anatomy from our other posts, the “meral spot” is a pair of false eyespots on the mantis’s raptoral appendages (the gonna-hurt-you limbs). If you held your arms in front of you, the meral spots would be on the inner sides of your elbows. The Smith’s Mantis Shrimp is well known for these spots because they are some of the most easily-identifiable: bright purple with a defined white outline. They give the Smith’s Mantis Shrimp its other common name, the Purple-spotted Mantis Shrimp. The body color of the Smith’s Mantis Shrimp is otherwise pretty similar to the Peacock Mantis, often bright blue-green and sometimes with red trim to each body segment. This species is a “smasher” and while it isn’t available as often as some other species, it is very sought-after by collectors when it is.

 

Chiragra Mantis Shrimp, Gonodactylus chiragra
This is one of the most common mantis shrimp that we receive at our store and is one of the best suited for aquarium life. It is the largest of the Gonodactylus genus of “smashers” but still only reaches about four inches in length. Unlike many other species, it is pretty easy to tell the difference between males and females. Male Chiragra Mantis Shrimp are usually blue-green in color while females are a mottled tan and cream. Both genders have a white meral spot that is far less obvious than the Smith’s. The most distinctive feature of this species regardless of gender is the light-colored sprinkles on the front corners of the carapace in the same place as the Peacock Mantis’s distinctive leopard spots.

 

Ciliata Mantis Shrimp, Pseudosquilla ciliata

This is one of my favorites. Not only is it a “spearer” when most of the more common species are “smashers” but they have one of the coolest defining traits…checkerboard eyes. All mantis shrimp have extremely complex eyes and three different “sections” can be seen on most of them. The Ciliata Mantis Shrimp also has vertical lines overlaying the horizontal segments so their eyes, if you can get close enough to see it, have a checkerboard-like plaid pattern on them. Most of the Ciliata Mantis Shrimp you’ll see in the aquarium trade are green or yellow but their color and even pattern can change every time they molt depending on their environment and the lighting.

 

Zebra Mantis Shrimp, Lysiosquillina maculata
It is easy to see where the Zebra Mantis Shrimp gets its name. It has alternating black and cream-colored stripes. It also has white speckled antennal scales and eyes. However, it is unique in that, like the Ciliata Mantis, the Zebra Mantis is a “spearer”. Rather than hiding in rockwork caves like most “smashers”, these mantis shrimp will build deep burrows in the sand or substrate, reinforced with mucus, where they wait to ambush their prey. This species also has the distinction of being the largest of all mantis shrimp. While most of the Zebra Mantis Shrimp that you’ll find available to aquarists aren’t much larger than any other species available yet, they can grow to over fifteen inches in length!

 

 

**A species to avoid: Gonodactylaceus ternatensis
Several mantis shrimp with bright orange meral spots are also sometimes available. Two of these, Gonodactylaceus glabrous and Gonodactylaceus graphurus are almost identical and can be hardy, fun mantis shrimp to keep. A third, Gonodactylaceus ternatensis, is a less suitable choice. When small, this mantis shrimp looks like a juvenile Peacock Mantis but is often found living within coral heads. To collect it, the heads are often broken and destroyed. With all of the other species available, please avoid G. ternatensis and stick with the species collected with safer, less destructive methods!

 

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These are just a few of the more common mantis shrimp other than a Peacock Mantis Shrimp but there are many other species that become available from time to time. So, don’t limit yourself if you are brave enough to head down the road to try these cool creatures!

• Smith’s Mantis Shrimp image used with permission from Roy’s List of Stomatopods for the Aquarium, ©2005 Roy Caldwell

 

Hiring staff for any job can be tricky. You need to make sure you have the right number of qualified employees to handle the job, not just a lot of employees on your payroll that eat into your bottom line or ignore the job you’ve given them. Choosing a clean-up crew for your saltwater aquarium is similar; you need to make sure you have the right snails and crabs and other cleaners for the tank without too many that can deplete your resources or just not even do the “right” work at all. “How many snails do I need?” is only part of the question; making sure you are getting the ones best suited to the job is just as important.

 

 

Job Description and Qualifications

 

Hiring an employee without knowing their qualifications or describing the job doesn’t make much sense, whether it is renovations on your home or clean-up within your aquarium. Not all snails eat algae. Not all snails that eat algae eat the same kind of algae. Not all “algae” is even algae at all. And snails may not even be the best (or only) cleaners for the job; “detritivores” that eat the leftover food and waste (“detritus”) are also necessary for keeping a tank clean and healthy. The first step to choosing a clean-up crew is to identify what the problem is that you’d like them to help you solve. Algae is normal in any aquarium and having a basic clean-up and scavenger crew is a good idea but beyond that, if you have a specific problem like a cyanobacteria bloom, hair algae, green water or other issues, you may need a solution beyond a few snails. You may be seeing a symptom of a larger problem like poor water flow or lighting quality and unless that problem is addressed, it will keep coming back no matter how many snails or other clean-up crews you throw at it.

 

What are the working conditions?

 

It takes a different kind of person to paint the walls of a house than it does to paint the cables at the top of the Golden Gate Bridge. It also takes a different kind of critter to clean up a nano-reef than it does a rock-filled bare-bottom aquarium or a deep sand bed. Some hermit crabs can have difficulty reaching into small crevices and some snails can’t flip themselves over if they tumble off of the glass or rockwork. Some snails, starfish and other animals popular in aquariums also eat other snails or invertebrates and corals. Are the animals you are choosing suitable for the environment you have?

 

It’s all in the job security

Contrary to popular belief, snails and hermit crabs are not disposable or short-lived or robotic lawnmowers that feed on nothing but salt and sunlight. If they have plenty of food and proper care, they can live for a long time. If they run out of the right food, they won’t survive so overloading a tank with cleaners to keep it spotless is only going to end up with losses. When snails and other cleaners die and decompose, they affect water quality. When water quality goes down, algae will bloom. When algae blooms, you’ll need to add more cleaners. Starting to see where this cycle goes wrong? Avoid the urge to overload on a massive cleanup crew and start with a basic foundation. Once you can observe where they need the help, supplement with some helpers for that purpose (like aerating the substrate, cleaning the glass, targeting hair algae or other trouble areas).

 

The magic number is…

 

Just like the old “inch-per-gallon” rule that is still floating around for fish, there are some stocking guidelines for clean-up crews. Some of the most common include a snail per gallon or a hermit crab per five gallons but again, this only works if that snail or hermit crab is suitable. To help you out in making some selections, we have basic Algae Packs with recommended tank sizes. You can start with the one closest to your tank size and give it some time. You can always supplement later or get a specialty algae pack to target a specific need like detritus or hair and buble algae. Remember, hiring is always an ongoing process!

 

 

The Mantis Shrimp, fabled ocean warrior and legend of internet Marine Biology humor (Thanks to The Oatmeal, and zefrank1) is the inspiration for research of new composite materials.  There are many applications for high performance impact resistant composite materials, and scientists and engineers are always looking for ways to make materials stronger, lighter and more versatile.  There is particular interest from the military and industry for stronger and lighter materials for armor, aircraft and automotive applications.

Why Study The Mantis Shrimp?

Most Reef Aquarium Keepers are aware of the hunting prowess of the mantis shrimp, and the weapons that they have developed to capture their prey.  There are two main types of Mantis Shrimp, grouped by the form and function of their specialized set of second legs, called raptorial appendages.  The Slasher or Stabber type of Mantis Shrimp have developed a sharp spear that it wields with Ninja like skill, earning it the nickname “Thumb Splitter” from fisherman who find them in their nets.  The Second type of Mantis Shrimp is the Smasher, given its name for the club like weapon that it uses to kill prey and open the hard shells of mollusks, crustaceans and gastropods.  It is the Smasher type of Mantis Shrimp that has scientists and engineers studying its design, looking for insight into designing lighter and stronger composite materials.

Real Life Beauty and the Beast

The Peacock Mantis Shrimp, Odontodactylus scyllarus, (which is actually neither a mantis, nor a shrimp) is a common species of Smasher Mantis Shrimp found in warm waters of the Indo Pacific and Indian Oceans.  Sometimes kept by the more adventurous marine aquarium keeper, this little Stomatopod is an amazing combination of striking beauty, and ruthless hunter.  The Peacock Mantis can fire its smasher club 50 times faster than the blink of a human eye, at the speed of a fired .22 caliber bullet.  The Club fires so fast, and with so much force, that it actually boils the surrounding water in a process called supercavitation.  The resulting strike and shock wave are devastating to their intended prey.  Mantis Shrimp have been known to break glass aquariums.  Chuck Norris punches with a wet noodle compared to the Peacock Mantis Shrimp.  What has researchers so interested is the amazing durability of the Peacock Mantis Shrimps striking club.  The Mantis can strike its club weapon thousands of times, with a striking force more than 1000 times its own weight without breaking.

The Latest Research

In a recently published study “Bio-Inspired Impact-Resistant Composites” in the Journal Acta Biomateriala, a team of researchers led by University of California, Riverside, in collaboration with University of Southern California and Purdue University studied the structure of the Mantis Shrimp’s smashing club.  The team was looking for design elements that could potentially be used to improve industrial composite materials that are used in things like; aircraft, military armor, protective helmets and automotive panels.  What they found in studying the Peacock Mantis Shrimps Club structure was a helicoidal arrangement of mineralized fibers, which made the club incredibly impact resistant and energy absorbing.  They then applied this design architecture into carbon fiber-epoxy composite impact materials, and tested the performance against similar composite materials used in the airline industry. The results showed improvement in the overall material toughness, with real promise for manufacturing in the future.

Future Research

 The Mantis Shrimp research showed so much promise, that the research group has been awarded a 7.5 Million dollar grant from the Department of Defense to continue their research.  Ongoing research will include looking at structural designs of more than 20 organisms, like bird’s beaks, snail shells, antlers of mammals and others.  All of which are made from relatively simple biological materials like Chitin and Keratin, yet show incredible mechanical durability.  You can read more about the team and their research on the UC Riverside website.

Does anyone else have an image in their heads of a military decked out in Peacock Mantis Shrimp armor, driving Mantis Smasher vehicles?  No, well you should, that would be awesome.

 

Until next blog,

Dave

Choosing the right aquarium salt mix to add to your tank can be can be a confusing process, especially if you’re new to the hobby. But, it isn’t as complicated as it may seem, you just need a little background info to get you on the right path to choosing the salt that is appropriate for your set-up.  

Salt in Freshwater Aquariums

Adding salt to a freshwater aquarium is not a necessity, but it is used by many aquarists as a treatment to add electrolytes to the aquarium water, and as both a stress reducer and a parasite deterrent. Basic Aquarium Salt is not the same as the formulated mixes used to make a brackish or saltwater aquarium. Aquarium Salt is simply Sodium Chloride, and does not contain minerals and trace elements like calcium and iodine like sea water mixes. Adding small portions of this salt can help to treat osmoregulatory stress, an imbalance or disruption in the exchange of salts and minerals between the fish itself and its environment. Stressful situations such as transport, disease, or injury can cause osmoregulatory stress, but if used properly, aquarium salt can increase blood and oxygen flow through the gills, helping the fish relax and heal. When used in higher concentrations for short time periods as a dip or bath, salt can help to build a the protective slime coat on the body, preventing parasites from attaching and even killing one-celled parasites like Protozoa, that may already be on the fish. While aquarium salt does have some benefits, it is not a necessary additive. Once introduced to the tank, salt does not evaporate out of the tank. It can only be removed with water changes and plants, inverts and other sensitive species may be negatively impacted if the concentration is allowed to rise. Read More »