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Author Archives: Frank Indiviglio

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Being born with a deep interest in animals might seem unfortunate for a native Bronxite , but my family encouraged my interest and the menagerie that sprung from it. Jobs with pet stores and importers had me caring for a fantastic assortment of reptiles and amphibians. After a detour as a lawyer, I was hired as a Bronx Zoo animal keeper and was soon caring for gharials, goliath frogs, king cobras and everything in-between. Research has taken me in pursuit of anacondas, Orinoco crocodiles and other animals in locales ranging from Venezuela’s llanos to Tortuguero’s beaches. Now, after 20+ years with the Bronx Zoo, I am a consultant for several zoos and museums. I have spent time in Japan, and often exchange ideas with zoologists there. I have written books on salamanders, geckos and other “herps”, discussed reptile-keeping on television and presented papers at conferences. A Master’s Degree in biology has led to teaching opportunities. My work puts me in contact with thousands of hobbyists keeping an array of pets. Without fail, I have learned much from them and hope, dear readers, that you will be generous in sharing your thoughts on this blog and web site. For a complete biography of my experience click here.

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Keeping the African Giant Filter Shrimp (African Fan Shrimp, Vampire Shrimp), Atya gabonensis, Part I

Hello, Frank Indiviglio here.

The African fan shrimp is not well established in the aquarium trade, but interest is growing.  I have maintained a group for approximately 2 years, and have found them to be fascinating, if a bit challenging in some respects.  Their mode of feeding is particularly interesting, but requires a bit of attention as to “presentation”…I’ll write more about that in Part II of this article.


This shrimp inhabits rocky streams along the west coast of Africa, from Senegal to Gabon.  It is also recorded from the east coast of South America; however, the genus is not well studied and these populations may represent a different species.  Their natural history is not well-documented.

African fan shrimp are heavily-built and reach 4 inches in length.  The first 2 appendages are equipped with feathery bristles which are swept back and forth when the animal is feeding.  Most in the trade are tan to dark brown in color, but blue, yellow, pink and red specimens show up on occasion.


Captive Habitat

The Aquarium

A well-filtered 10 gallon aquarium will comfortably house 4-5 shrimp.  They seem quite social; I have keep 12 in a 55 gallon aquarium.  The tank should be well covered, in case they decide to explore by climbing filter tubes or heaters.

Heat and Light

I keep my fan shrimp at 76 F; their temperature range is reported to be 74-88F.

African fan shrimp only leave favored retreats at night, and then infrequently.

A Night Glo bulb  or similar bulb will allow you to view their nocturnal activities.


A rock or gravel substrate is preferable, as such is what would be found in their native habitat.  However, people keeping these shrimp on sand report no problems.  They do not negotiate bare-bottomed tanks well, and seemed stressed by the effort.

Physical Environment – Habitat Type and Terrarium Decorations

African fan shrimp are very shy and retiring, and require suitable shelters if they are to thrive.  Mine seem quite specific in their choice of a retreat – once they settle in, they remain within the same cave or shelter, even if others are available.  I have observed several shrimp to occupy the same small caves for 18 months.

They will utilize rock caves or artificial structures and ornaments.  Despite their need for privacy, the shrimp seem unconcerned about being on view through glass…caves positioned near the aquarium’s glass will allow easy observations.  They prefer a “tight fit” over a spacious cave, and many will remain within one shelter, usually in physical contact with one another, if able.  I’m not sure if they prefer to live in groups (field studies are in short supply) or not, but they certainly do well when provided with a cave that allows them to congregate.


Hailing as they do from fast-flowing streams, fan shrimp likely have high oxygen requirements, so be sure that your tank is adequately aerated.

They should be maintained at a pH of 6.5-7.4.  I use soft water, but this is not based on field research (in fact, water in rocky streams tends to be hard).

Like many invertebrates, fan shrimp are extremely sensitive to ammonia, and to copper and other chemicals that are found in fish medications.

I’ll finish up with feeding and  pass along a few observations next week.

We have much to learn about these and other fresh water shrimp… please write in with your questions and observations. Thanks, Frank Indiviglio.

A video of an African fan shrimp in the process of feeding is below:

Introducing a Catfish Fancier’s Dream: the Frog Mouth or Angler Catfish, Chaca bankanensis – Part 2

Click: Introducing a Catfish Fancier’s Dream: the Frog Mouth or Angler Catfish, Chaca bankanensis – Part 1, to read the first part of this article.

The Natural Habitat
The waters in which the frog mouth naturally dwells are almost always located within rainforests, and are quite acidic and soft (“black water”, in the trade). This habitat supports far fewer species of bacteria than most, a fact that may explain this fish’s susceptibility to bacterial and other infections in captivity.Animals hailing from low-bacteria environments lack immunities to micro-organisms that are commonly encountered outside of their natural habitats. I have faced similar problems when rearing other animals from unique habitats – desert-adapted tortoises and penguins are both very delicate in this regard.

Establishing the Frog Mouth Catfish in the Aquarium
I strongly recommend using Marc Weiss Co. Keta-Peat Nuggets in the frog mouth aquarium. Added to the filter, this product will help soften the water, reduce bacterial and algal growth, and create a “black water” environment for your fish. Aquarium Pharmaceuticals pH Down will help to maintain an acidic environment. The waters from which this species originates average 3-4 in pH, but a pH of 6 works well in captivity.

Light and Shelter
The aquarium should be dimly lit, as the frog mouth naturally inhabits muddy waters and is uncomfortable in bright light.

A bed of oak leaves thick enough to hide the catfish is essential if it is to adapt and behave normally. The leaves mimic the cover under which this fish spends most of its time, and will also assist in maintaining a low pH. The frog mouth catfish is most comfortable at temperatures of approximately 77°F.

The frog mouth is a sizable fish that consumes large prey, and so likely produces a good deal of nitrogenous waste. Careful attention should be paid to filtration – the fact that it inhabits muddy waters does not indicate a tolerance for poor water quality. However, the filter’s outflow should be slow, as these fish are not strong swimmers and are native to still and slow- moving waters.

In terms of diet, the frog mouth is a fish specialist, although it has been reported to feed upon earthworms and tadpoles as well. Neither I nor those I have spoken with could induce it to accept earthworms, but an aquarist in Japan reported that her frog mouth fed readily upon freshwater shrimp.

As this fish is still considered a delicate captive, and rarely if ever spawned in captivity (the related Chaca chaca has occasionally been bred), you might consider adding aquarium fishes hailing from Southeast Asia to the diet, along with guppies, minnows, goldfish, platies, mollies and other easily bred species. Until we learn more about its needs, dietary variety will remain an important key in maintaining this fish in captivity.

Due to this specie’s extreme sensitivity to diseases and pathogens that might be carried, unnoticed, by other fishes, I pre-treat all feeder fish with Methylene Blue.

Research Needed
It has been reported, anecdotally, that the frog mouth catfish wiggles the barbels near its mouth in order to lure fish within striking range. Certainly the barbels do move about, but to my eye this seems to be a sensory rather than food-luring behavior. Documenting true luring, as in the manner of a marine anglerfish, would be an interesting project for the aquarist fortunate enough to acquire one of these fascinating animals.

The Standard Catfish Warning!
Please be aware that the spine next to the dorsal fin can inflict a painful wound.

We have a great deal to learn about this fascinating catfish and its relatives…please write in with any observations or questions you may have. Thanks, until next time, Frank Indiviglio.

You can read more about the natural history of this fish and view a picture at:

Introducing a Catfish Fancier’s Dream: the Frog Mouth or Angler Catfish, Chaca bankanensis – Part 1

Hello, Frank Indiviglio here.

Those who believe that one must look to the sea for really bizarre aquatic life forms have no doubt missed the frog mouthed catfish. If ever a freshwater fish were to qualify as a true oddity, something along the lines of a marine anglerfish, it is certainly this Southeast Asian native. In its appearance, movements (“walking” rather than swimming) and ability to vocalize (the sound it makes, “chaca-chaca” has given rise to the Genus’ name), this unusual creature seems to straddle the line between fish and amphibian.

Catfish Heaven
I first came upon the frog mouth catfish in a book translated from Japanese. As I learned upon visiting Japan, catfishes of all types are incredibly popular there – one store I frequented had over 50 tanks of various species! The fact that Prince Akishino (son of Emperor Akihito) studies catfishes has increased public awareness and appreciation of these often over-looked creatures.

Fortunately, I had a number of contacts in Japanese pet stores and public aquariums…this was paradise for me, and I was able to learn a great deal about catfishes that I had not encountered before, including the frog mouth.

Description and Range
The frog mouth catfish is a squat, mainly brownish fish, possessing a huge mouth that gives a square shape to the head. The tiny eyes are nearly invisible, and from the wide head the body tapers sharply. Cutaneous flaps of skin help to break up the body’s outline and add to the camouflage effect as the fish lies on the river bottom waiting for prey.

Native to southern Thailand, Malaysia, Sumatra and Borneo, the frog mouth catfish is not common in the US pet trade but is becoming increasingly available. Best kept by those with some aquarium experience, it is well worth searching for.

A Shy and Sedentary Captive
Although not an active fish, the frog mouth does require quite a bit of room, as it reaches nearly 1 foot in length and is stressed by close confinement. A 30 Long Aquarium is the minimum that I would recommend for a single animal, with a 55 Gallon Aquarium sufficing for a pair or possibly a trio. It spends most of its time hunkered down on the bottom of the aquarium, preferably under cover of some sort, and even at night does not actively hunt for food.

The frog mouth catfish is best kept alone, as it can swallow prey nearly half its own length. Also, it is very prone to stress and does not do well in aquariums housing actively swimming fish.

Click here: Introducing a Cafish Fancier’s Dream: the Frog Mouth or Angler Catfish, chaca bankanensis – Part 2, to read the rest of this article.

Why Keep Fish and Aquatic Invertebrates? – some thoughts for new and experienced aquarists

Yesterday and Today
Hi, Frank Indiviglio here. When I first became involved with aquatic animals, it seemed that most people kept aquariums as an offshoot of a long-seated and intense interest in fish and other animals. Especially where marine organisms were concerned, the difficulties inherent in keeping all but the hardiest of creatures discouraged those with only a passing curiosity.

However, a wealth of information and technical advances has now greatly simplified life for those desiring an aquarium of their own. More and more, people are drawn to the hobby because of the sheer beauty of the animals that can be brought into their homes. It has been my experience that such people usually develop a deeper interest in their pets, and a sincere concern for their well being.

Expect Great Rewards
However you might come to aquarium-keeping, and whether you decide to focus on fresh water or marine animals, or both, you will gain an insight into worlds that have largely been beyond your reach. Even when keeping common species in the most basic aquarium set-ups, you will be privy to the secret lives of a host of fascinating organisms. The thrill of a first breeding success, or the observation of a rarely seen or even unknown aspect of animal behavior, is quite hard for me to put into words, even after all this time – but trust me, it is not to be missed.

The Captive-Wild Link
The life history details of many, if not most, of the world’s fishes and aquatic invertebrates are virtually unknown. The aquarist who takes the time to properly maintain both common and unstudied creatures stands an excellent chance of contributing to our understanding of them.

Most aquatic animals will exhibit a full range of natural behaviors only under ideal captive conditions. You must, therefore, learn as much as you possibly can about both the natural history and captive husbandry of your pets. Considering the destructive effects of human activities on wild animals and their environments, we should remember that every bit of information that is gleaned about a creature’s behavior will contribute, in a very real way, to its future survival in the wild.

Other Rewards
Aquarium keeping usually stimulates deeper interests in a wide range of related subjects. You, and those with whom you share your passion, will want to learn more and more about the animals that you keep – how they live, what prospects they have for continued survival and what must be to protect them.

For young children, especially those largely isolated from nature, an aquarium can be a call to new worlds, interests and careers (I am a case in point). I have observed that elderly people often find this hobby quite stimulating, and the sense of being responsible for the well-being of other creatures can become a healthy influence in their lives. My own grandfather started me off in the early 60’s, with seahorses, octopus and other creatures (often rescued from the pot at NYC’s Fulton Fish Market!) and my mother continues to pile up new and interesting observations on her own fish, invertebrates and aquatic amphibians.

Contributions You Can Make
Upon entering the world of zoos and public aquariums, I was quite surprised to learn that the observations of “non scientists” are the source of much of what is known about aquatic animals. Important facts are routinely uncovered by amateur naturalists and hobbyists observing their pets or exploring natural areas.

The potential for discovering new facts and, indeed, new species, is greatly increased for those with an interest in invertebrates (for example, a new species of centipede was recently discovered in NYC’s Central Park, on ground that I and millions of others trod daily). We are unaware, even to the nearest degree of magnitude, of the number of invertebrate species that inhabit the world, and are even more ignorant as to how they live their lives.

Record everything and anything that you observe as you pursue your hobby. You may wish to employ the help of interested friends and relatives in your endeavors. I have noticed that children and the elderly are often especially fascinated by live animals, and may gladly spend long periods of time watching your aquariums. Volunteers have long served as an “extra pair of eyes” for me in my work at zoos and aquariums, and I never cease to be amazed at all they reveal to me.

Observe, Discover and Share
Above all, be generous in sharing what you have seen and learned with others. Become involved with special interest organizations, and publish your findings whenever possible. The fact that an observation first appears as a note in an informal publication does not in any way lessen its importance – consider that Wallace’s theory of evolution, which closely paralleled Darwin’s, was revealed in a letter written to the latter, and spurred Darwin to publish his own findings.

The local newsletters of aquarium organizations are often the starting points for researchers interested in particular animals or environments. Please do not be trapped into believing that you must be a “professional” in order to contribute – as you will discover by reading about any animal, very little can replace direct observation as a means of discovering new information.

Using This Blog to Draw Attention to Your Ideas and Observations
Perhaps we can utilize this blog as a springboard for new ideas and facts. I would appreciate hearing about your observations of aquatic creatures. If you have seen something that you believe to be unique or perhaps unrecorded, please feel free to write in …I’ll be happy to look into it further, and to advise you on the possibilities of publishing or pursuing it further. Please do not hesitate to write in if you are unsure – over the years, observations that seemed not at all unusual to me have turned out to be quite the opposite – sometimes it’s hard to tell. Thanks, until next time, Frank.

Brittle Stars, Sea Stars and Sea Urchins – an Introduction to Some Popular Echinoderms

Frank Indiviglio here with an introduction to Echinoderms.

Sea stars, or starfishes, are perhaps the most familiar of the Echinoderms (a phylum containing over 7,000 marine species), and many adapt well to aquarium life.  Most people are quite surprised to realize that they are active, interesting predators that routinely exhibit a wide variety of behaviors in the aquarium.  Many are also useful scavengers, but all are predatory in nature and, depending upon the species, will consume mollusks, coral polyps and other sedentary invertebrates.

Red-knobbed Sea Star, Protoreaster lincki
Red-knobbed Sea StarWhen picturing a sea star, many people think of the simple reddish-orange animal so often seen as a dried curio in beachfront shops.  However, many are fantastic in appearance and coloration.  The Red-knobbed Sea Star, with brick-red dorsal spines set off against a dazzling white background, is a case in point.

Native to the Indo-Pacific region, this perennial aquarium favorite reaches a length of 12 inches and is capable of consuming quite large mollusks.  It is best fed by placing a piece of clam, scallop or mussel directly below the body, although it is quite active and capable of finding food on its own.

Although sea stars are quite adept at sensing and locating food, they respond more slowly than do most fish.  Therefore, they will usually remain hungry in a mixed-species tank unless care is taken to see that food is placed directly below each animal.

Brittle Stars
Black Brittle StarBrittle stars bring the word “bizarre” to mind instantly, even to those well acquainted with the sea’s curiosities.  They react very quickly to the scent of food, and their long, slender arms thrash wildly about as they begin to explore.  It is quite a sight to see a tank housing several of these normally sessile creatures suddenly come to life – the many sinuous arms seem to take on a life of their own, yet the animals glide unerringly toward the source of the odor that aroused them.

Brittle stars are harmless to most other creatures and are extremely valuable scavengers.  Perpetually hungry, their thin arms can get into the tiniest of crevices between coral heads and other places where bits of uneaten food might otherwise go unnoticed.

Sea Urchins
These slow-moving, spiny invertebrates are often encountered in tide pools, and are worldwide in distribution.  The spines of all are effective weapons, and many secrete venoms that are as yet not well-studied.  Hot-water baths seem to assist in alleviating the sting caused by most species, but handle all with extreme care.

With over 800 species identified to date, urchin enthusiasts have much to celebrate.  Many unusual species are commercially available, including the Long-spined Sea Urchin, Diadem antillarum and the Pencil Urchin, Heterocentrotus mammillatus. Both feed primarily upon algae, but will also consume bits of fish and shrimp.  The Long-spined Urchin is armed with extremely sharp spines, much to the chagrin of bathers in tropical waters.  The Pencil Urchin is well named – its spines, less numerous than those of other urchins, are very thick and blunt-ended.

Wave your hand above a captive or wild sea urchin and you will likely be surprised at how quickly the seemingly inert beast responds.  A shadow or object passing overhead is viewed by an urchin as a predator, and all the spines are oriented to face the threat.  Although parrot fish, sea otters and wolf fish are adept at clipping off urchin spines or turning the animals over to expose the soft underbody, the defense is, in general, foolproof.

Despite their slow-moving ways, sea urchins are quite active and seem bent on getting into every possible nook and cranny in their aquarium.  Be sure to check that they do not wedge themselves too tightly into small corners, or tumble backwards into coral and become stuck.

I’ll cover individual species in depth in future articles.  Until then, please write in with your questions and comments.  Thanks, Frank.

You can read more about sea urchins, sea stars and their relatives at: