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.

Hey everyone, Eileen again with a quick and interesting bit of news!

One of our former TFP colleagues recently shared with us an exciting experience, and I wanted to pass it along. Erica Palmer, an assistant curator at Coral World in St. Thomas and a former That Fish Place Fish Room Supervisor, knew that the story would peak our interests, and she is sooo lucky for being able to be a part of it.

During my college days, I participated in loggerhead sea turtle nesting studies and research along the South Carolina coast. Our volunteers would walk the beach every morning looking for the telltale “crawl”, the tracks made by the female turtle as she crawled up the beach to lay her nest, but we very rarely ever caught a glimpse of the turtle in action.

Visitors to a beach resort in the Virgin Islands got to witness the proverbial “Holy Grail” of turtle nestings when a very rare Leatherback Turtle crawled right up to the line of beach chairs in front of guests and hotels workers alike to lay her eggs!  Erica  is quoted in an article as saying that the rare late season nest is likely the last one that this turtle had the urge to lay before heading back out to sea to the turtles’ feeding grounds. The nest is now under surveillance by the resort to help keep the eggs safe. The nest is due to hatch in mid to late September.  I hope she sends us an update!

Visit the article on National Geographic’s website for more information on this exciting event: http://blogs.nationalgeographic.com/blogs/news/chiefeditor/2009/07/leatherback-turtle-virgin-islands.html

Eileen here.

One of the most iconic images of a jellyfish, the one most people think of, is that of a dome-shaped animal with long flowing tentacles drifting through the water. For the aquarium community however, this is not the one that we usually see in our tanks. A far more common aquarium jellyfish is the Upside-down Jellyfish.

There are about five different species of Upside-down Jellyfish, found mostly in the Caribbean and tropical western Atlantic Ocean. One of these species in particular, Cassiopea andromeda, has made its way to the Hawaiian Islands and seems to have established itself as a nuisance in waters around the state. It is another species, Cassiopea frondosa, that is usually found in the aquarium trade.

All jellyfish are planktonic by nature, meaning they move with the flow of the water instead of swimming against it. The Upside-down Jellyfish does not actually live in the water column like most other jellyfish. Instead, they use their bell much like an anemone uses its foot to attach to the bottom of a shallow environment like a lagoon, mangrove swamp or sand flat. While this attachment isn’t nearly as strong as an anemone, it helps the jellyfish to remain relatively stationary with its tentacles pointed up towards the surface.  The bell will often pulsate slightly to create a weak water flow over its tentacles which the jellyfish uses to filter-feed small food particles from the water. Upside-down jellyfish also have stinging cells known as nematocysts on its tentacles which it can use to stun larger prey. This feeding helps supplement its diet, but most of the jellyfish’s nutrition comes from the symbiotic algae in its tissue. The sunlight filtering through the water feeds the algae, which in turn produces food for the jellyfish while the jellyfish provides protection for the algae by keeping it alive in its tissue.

Upside-down Jellyfish are one of the easiest types of jellyfish to keep in home aquariums but still require special care and attention. As these animals can reach a diameter of almost a foot across, they should have plenty of flat, open sandy area to spread out. They also need very bright light to feed the algae in its tissue as well as periodic target feeding with foods like brine shrimp, baby brine shrimp, cyclops, zooplankton, phytoplankton and dissolved organic foods. The flow in the tank should be moderately low and any filter intakes should have some sort of covering to make sure the jellyfish doesn’t get sucked up by the current. The stinging cells on their tentacles can also harm other tankmates; do not keep with any shrimp, gobies or other invertebrate or small fish that can become food! These nematocysts can also sting aquarists so take care not to come into contact with the tentacles.

The flower-like appearance, unusual behavior and relatively easy care are making this jellyfish gain in popularity among home aquarists. With some extra TLC and research, Upside-down Jellyfish can truly be a unique addition to a home aquarium!

Patty here. Often brackish fish are a hard sell to people on the market to start an aquarium.  Fish appropriate for brackish systems don’t tend to be as colorful or as easy to mix in communities as many other types of fish, or so many think.  But though these fish are often banished to a remote corner of the fish shop, and often seem too complicated to keep, there is one fish in particular that may be the one to convince you to try your hand at a brackish system.

Archerfish are a common offering in the trade, but their brackish classification and simple beauty may keep them hidden from the view mainstream aquarium enthusiasts.  They are native to India, Southeast Asia, Australia and other countries of the western Pacific.  They prowl through estuaries and mangroves mostly, but may be found upstream in full freshwater or on reefs periodically.

The Banded Archerfish (Toxotes joculatrix), the species commonly offered in the trade, is modestly colored with a tan-grey dorsal area and a pale silvery-white body.  Bold black markings camouflage them from prey and predator above.  They have a compressed body with a flat area from the dorsal fin to the mouth which allows them to move along just under the surface of the water. The mouth is angled upwards.

The most fascinating thing about Archers is their unique and famed ability to shoot their prey.  These fish are skilled predators that are able to snipe insects from branches and foliage 3-5 feet above the surface.  The fish shoots several droplets of water, quickly correcting any error in trajectory and aim to knock prey from the safety of the canopy to the water’s surface where the fish devours its meal.  They may also leap from the water to catch prey that is within reach or dine on small shrimp and fish in the water, but in the wild they commonly swim in groups of “shooting parties”, working together to pick off unsuspecting bugs. With the right set up, you can witness this behavior in your own living room!

This species can reach a max size of up to 12 inches in the wild, so habitat size is the first thing to consider.  They can be expected to reach about 8-10 inches in captivity, and the minimum size aquarium is 55 gallons.  Larger, deeper tanks are better!  Though juveniles may tolerate freshwater environments for some time, as the fish mature a brackish level of 1-2 percent will be necessary (roughly 8-15 teaspoons of aquarium salt per 10 gallons).  The ideal set-up is one that allows for plenty of room to swim and terrestrial areas or areas of open air (like a large tank filled half or 3 quarters full/paludarium set-up) to make the fish happy and allow for a great show! 

You can furnish the tank with salt tolerant vegitation both in terrestrial areas and submerged, driftwood, root wood, rock, and sand or fine gravel.  Good filtration is a must! Though the fish are hardy, they like clean water like that where they are found in the wild.  Once in their new home these fish will quickly resume normal hunting activities, and a batch of live crickets will make for some sport.  These fish will also eat frozen and freeze-dried foods.  Other fish can also be housed with archers as long as they are tolerant of brackish conditions, large enough not to be considered prey, and not overly boisterous.