That Fish Blog – Aquarium Advice and Information

Hello, Frank Indiviglio here.  Please see Part I of this article for information on the care of freshwater shrimps, and for profiles of other popular species.  Today I’ll highlight a few beautiful, lesser-known species in the genus Caridina and Brazil’s yellow-bellied grass shrimp.

Red-Nosed or Rhino Shrimp, Caridina gracilirostris

A relative newcomer to the trade, the rhino shrimp is already quite popular.  In its native India, this shrimp inhabits salt marshes and, while it thrives in freshwater, it will not reproduce without exposure to brackish water.  It also differs from other shrimps in its propensity to swim rather than crawl.

Rainbow Shrimp, Caridina babault

This ¾ inch beauty occupies a huge natural range – India through Malaysia – and occurs in an equally impressive range of colors – blue, red, rust, yellow and variations thereof. 

Black Forest Shrimp, Caridina sp.

Dwelling in Thailand and perhaps elsewhere in Southeast Asia, this shrimp-fancier’s favorite is boldly marked with a broad white band about the body and a white-tipped head.  At 1 inch in length, it is large enough to make quite an impressive display when kept in groups.

Brazilian Yellow-Bellied Grass Shrimp, Palaemon pantanal

One of the few South American species in the trade, this hardy 1.5 inch long fellow is best kept in cooler waters than the aforementioned species, and is an excellent choice for an outdoor pond.  It does best at temperatures of 68-70 F, but will remain active and healthy in colder conditions as well.

Further Reading

For information on keeping amano, cherry and bamboo shrimps, please see An Introduction to Freshwater Shrimps.

To learn more about a truly unique shrimp, please check out my article Keeping the African Giant Filter Shrimp.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

Palaemon serratus image referenced from Wikipedia and originally posted by Enrique Dans.

Bamboo Shrimp referenced from Wikipedia and originally posted by Faucon

Hello, Frank Indiviglio here.  I’m partial to snails…from tiny stream dwellers indigenous to the spray zone of one waterfall in NY to the huge lumbering African land snails, all that I’ve worked with have been fascinating.  But aquarists often have a love/hate relationship with snails, searching for one that will consume unwanted algae while not eating plants or over-populating the tank.  Enter the olive nerite, a/k/a black marble or Alexander snail (Vittina usnea, formerly Neritina reclivata alexandre).

Natural History

Amazingly, this adaptable snail, native to brackish water habitats in Florida and throughout the Caribbean and Gulf of Mexico, thrives equally well in fresh, brackish or marine aquariums.  It will, however, only reproduce in brackish or marine waters, and so is an ideal choice for freshwater aquarists who fear snail population explosions. 

In the wild, the olive nerite ventures far up rivers, often being found miles away from the sea.  It seems unlikely that such a small creature would migrate back to the ocean to reproduce, so it may breed at the river’s bottom, where denser marine waters penetrate at high tide.  It is theorized that this unusual mollusk may be in the process of evolving from a marine to a purely freshwater creature.

Olive Nerites in the Aquarium

Another point to recommend the olive nerite is the fact that it feeds only upon the brown and green algae that often coats plant leaves, rocks and aquarium glass, and leaves living plants untouched.  When algae populations decline, its appetite can be easily satisfied with algae wafers  and Spirulina discs.

The attractive shell of marble-sized olive nerite is often colonized by tiny barnacles, adding to its interesting appearance.  They are as resilient to environmental conditions as they are to habitat changes, doing well at temperatures ranging from the upper 40’s to the upper 90’s (F) and in waters of 6.3-8.4 in pH.

Related Snails

Two purely marine relatives of the olive nerite, Neritina  funiculata and Vittina luteofasciata, are sometimes offered for sale as well.  They have wider appetites than their more popular cousin, but do best in marine aquariums that support red and brown algae.

Further Reading

Detailed information and a key to the snails of Florida has been posted by the Florida Museum of Natural History at http://www.flmnh.ufl.edu/malacology/fl-snail/snails1.htm.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

Image Neritina reclivata is of a related species, referenced from Wikipedia and originally posted by ictheostega.

Hello, Frank Indiviglio here.  Until recently, freshwater shrimp have largely been ignored in the US aquarium trade. I’ve kept a few native species over the years, and was awed by some huge, long-clawed specimens that I collected and released in Costa Rica.  But it wasn’t until I visited Japan several years ago that I became aware of the scores of small, colorful Asian and South American shrimps that were being bred and sold regularly there.  Happily, most of those I came across at that time are now well established in the trade here in the USA.

Environment and Tankmates

The following shrimps will co-exist with one another, provided the dietary needs of the specialists are met.  All thrive at temperatures of 74-80 F and a pH range of 6.5-7.5.  They do best in heavily planted aquariums with moderate water flow and, like many invertebrates, are very sensitive to ammonia.  Many species appear somewhat social, congregating together, and most gravitate to and forage on driftwood if such is provided. 

Freshwater shrimps may be housed with small, peaceful aquarium fishes, but will be attacked buy predatory species and crayfishes.  I have had very good luck in keeping breeding groups with guppies, armored cats (Corydoras spp.) and hill stream, coolie and yo-yo loaches.

Feeding Shrimp

All the following species consume algae, with some favoring hair algae, but they also take a wide variety of flakes, pellets, carrion and organic detritus.  Shrimp of all types are seemingly always foraging, day and night, and should be provided with a wide variety of food options. 

In addition to live algae, I offer freshwater shrimps tropical fish flakes, shrimp pellets, spirulina tablets and live brine shrimp.  If water quality is not an issue, it is also a good idea to allow them to feed upon an occasional small, dead fish.

Amano or Japanese Marsh Shrimp and Relatives, Caridina multidentata

This East Asian import was one of the first species established here, and is still a favorite.  Please see the article referenced below for further information.

The closely related dwarf blackberry shrimp and emerald green shrimp, both native to Thailand, are beautifully patterned and may hybridize with the amano shrimp.  All three prefer to feed upon hair algae, but will take a wide variety of other foods.

Bumblebee Shrimp, Caridina trifasciata

Another Japanese import, the bumblebee is strikingly marked in black and white and possessed of a squat build that makes it seem larger than its ¾ inches.  Voracious scavengers as well as algae eaters, a group of these beautiful shrimps makes a spectacular display.

Orange Halo or Bee Shrimp, Caridina sp.

Favoring hair algae, this native of Thailand is bright orange in color and reaches ¾ inches in length.  In common with its relatives, the orange bee shrimp does best in groups.

Pearl or Snowflake Shrimp, Macrobrachium mirabile

A giant among the dwarf shrimp, this long-clawed species may top 2 inches in length.  It hails from India, where it favors the brackish water of river mouths.  Captives do fine in freshwater, however, and make excellent scavengers.  Despite its size, it is inoffensive to its smaller cousins.

Further Reading

For information on keeping the popular amano, cherry and bamboo shrimps, please see An Introduction to Freshwater Shrimps.

To learn more about a truly unique shrimp, please check out my article Keeping the African Giant Filter Shrimp.

Next time I’ll cover a few species that are rather new to the trade, as well as some more colorful and unique favorites.  Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

Hello, Frank Indiviglio here.  With rigid bodies propelled “helicopter fashion” by tiny fins, the 33 marine species that comprise the Family Ostraciidae are quite amusing as they motor about.  Their appeal is heightened by an “alert” face and, in many, horn-like projections at the head and rear.  Some species grow quite large and require unique diets, but several make interesting, appealing aquarium subjects.

A hard bony carapace protects cowfish relatives from attack by many predators.  However, all are slow moving, and their rapidly undulating fins seem to draw attacks from smaller fish.  Oddly enough, the skin over their rigid protective plates is quite sensitive.  Be sure to watch your specimens closely, lest wounds inflicted by tiny fishes go un-noticed and lead to infection or stress-related diseases.

A 40+ Year Old Memory of a Long Horn Cowfish, Lactoria cornuta

A brilliant yellow body highlighted with blue spots and set off by “horns” at the head and rear renders this droll fish instantly recognizable.  I have a soft spot for these comical fellows.  Back in the early 1960’s, when my grandfather lured me into keeping marine fishes, a long horn cowfish was my first exotic species.  Armed with pioneering marine aquarist Robert Straughan’s 1959 classic The Salt Water Aquarium in the Home, we frequented the 2 NYC aquarium stores (1 in the Bronx, 1 in lower Manhattan) that stocked marine fishes.  Shipments were irregular at the time, but we lucked out on 1 trip with a gorgeous cowfish. 

All-glass tanks were not yet available, so we installed our prize in a large plastic aquarium, where he impressed me greatly by being the only one of  my early purchases to survive my clumsy attempts at marine fish husbandry! 

Slow feeding and peaceful (although aggressive towards other cowfishes), the long horn is one of the few fishes that I was able to house with another long-time favorite, the Atlantic seahorse. 

Hovercraft Boxfish, Tetrosomus gibbosus

This species’ mode of swimming truly fits its name, with only the fins fluttering, propeller-like, as the rigid body moves along.  They are extremely inquisitive, seeming to notice and examine all happenings within and outside of their aquarium.

Maturing at a mere 4 inches in length, hovercrafts are an excellent choice for those lacking space to house long horn cowfishes and other large species.  They are, however, slow to feed, and so their condition should be monitored closely…the stomach areas of underfed boxfishes will rapidly take on a sunken appearance.  However, when housed with other small, methodical feeders (seahorses and pipefishes are worth a try), hovercrafts do quite well.

Husbandry Considerations

Many cowfish relatives are, despite their “apparent calmness”, quite excitable.  Frightened specimens will release a skin-generated poison into the water.  Known as ostracitoxin, this secretion is toxic to other fishes, and, in close quarters, to the toxin-producer itself. 

Establishing cowfishes in an aquarium before adding other species, and choosing only slow-moving, peaceful tank-mates, will go a long way in preventing disasters.  In a dark room, always turn a small room light on before using the aquarium canopy light.

In the wild, cow, box and trunkfishes feed largely upon algae and sessile invertebrates (i.e. sponges, tube worms).  Captives take a wide variety of frozen, freeze-dried  and algae-based foods, along with live brine shrimp, mysids and blackworms.

Further Reading

For further information on the long horn cowfish, please see Species Profile: the Long Horn Cowfish.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

Image referenced from Wikipedia and originally posted by LASZLO ILYES

Hello, Frank Indiviglio here.

In Part I of this article we examined some important points concerning freshwater stingray ownership. I’ll continue here with more husbandry tips and a look at the natural history of two unique species.

Selecting an Individual: Health

Large rays may have been collected via hook, do not ship well, and usually arrive in very poor condition. Check those over 12 inches in diameter carefully. Their adjustment to captivity is much less successful than that of smaller individuals.

Do not purchase a stingray whose fins are curled upwards along their margins. For reason as yet unknown, such animals invariably expire in short order.

Identifying the Various Species

It is important that you lean to identify the commonly available species before making a purchase. Animals in the genus Dasyatis, commonly sold as “freshwater stingrays” are actually native to brackish waters (river mouths) and may fare poorly in freshwater aquariums. Others, including ceja, antenna, tiger and China rays, have unique feeding and water quality requirements, and make quite delicate captives.

The hardy, popular common or motoro ray (Potamotrygon motoro) exists in 6-8 distinct color morphs, and is difficult to identify based on appearance alone.

Diet

Freshwater stingrays have fast metabolisms and need 2-3 feedings each day; dietary variety is vital to good health.

Live blackworms, ghost shrimp, crayfish, earthworms and small fishes are necessary for newly-acquired specimens. Eventually, most can be habituated to accepting canned invertebrates and animal-based frozen foods, but live animals remain an important component of the diet.

Stingray Tankmates

While rays often get along well with each other and certain other fishes, the usually benign suckermouth catfishes (i.e. Plecostomus spp) present an unusual problem. They often latch onto stingrays’ backs, sucking at the skin and causing lesions and stress-related ailments. The reasons for this behavior have not yet been thoroughly investigated.

Legality

You would be well-advised to check the legality of stingray ownership, as 8-10 states currently prohibit the keeping of freshwater species.

A Freshwater Ray in the USA?

Most freshwater rays offered in the trade hail from South America, but others may be found in Asia, Africa and Australia.

Interestingly, Florida’s St. John’s River is home to a population of marine rays that have adapted to life in fresh water. The species involved, the Atlantic stingray, Dasyatis sabina (please see photo), is known to forage in river mouths, but the St. John’s River population is the only one that has become independent of the sea, even breeding in freshwater.

An Amazing Giant

Southeast Asia is home to the world’s largest freshwater stingray, Himantura chaophraya. In January of 2009 a researcher captured a massive specimen in Thailand’s Meaklong River. Spanning nearly 9 feet across and weighing an estimated 660 pounds, the giant appeared pregnant and was released unharmed.

A Hands-On Experience with Stingrays

Please be sure to visit That Fish Place/That Pet Place in Lancaster, PA (the world’s largest pet store) for a chance to hand feed our friendly marine stingrays.

I’ll cover the care of freshwater, marine and even some native stingrays in detail in future articles. Until then, please write in with your questions and comments.

Thanks, Frank Indiviglio

Further Reading

You can learn more about Southeast Asia’s spectacular giant freshwater stingray here.

Please also check out the book, Freshwater Stingrays for more on captive care.

Image referenced from Wikipedia and originally published by the user Abigor.