That Fish Blog – Aquarium Advice and Information

Classification

More than 200 species of moray eels, all classified within the Family Muraenidae, have been described.  Like the familiar American eel, morays are considered to be true eels of the Order Anguilliformes.  The Superorder to which all eels belong, Elapomorpha, contains over 800 species, including the decidedly “un-eel like” tarpon.

Natural History

Although usually associated with tropical and subtropical habitats, a number occur in temperate seas, and several enter brackish and fresh water on occasion.  Ranging in size from the red-faced eel (Monopenchelys acuta), which reaches only 8 inches in length, to the 12.5 foot long giant green moray (Strophidon sathete), all share a similar body pattern and habits.  The latterly flattened body allows them access to the narrow caves and crevices that form their home base.  Many spend their entire lives within close proximity to a favored shelter, leaving only to mate and foraging nearby.

Some Interesting Facts

Morays can reach quite high densities in suitable habitats, accounting for nearly 50% of the carnivore biomass on some reefs off Hawaii.  Although nowhere considered a delicacy, moray eels are eaten on occasion, and instances of fatal poisoning (ciguatera) have been reported in the Philippines.  A number have unusual life histories…the leaf-nosed moray (Rhinomuraena quaesita) begins life as a dark blue-and-yellow colored male and later transforms into a black-and-yellow female.

Diet and Feeding

Moray eels are carnivorous, and in captivity will readily accept frozen silversides , sand eels , clams  and other fish, crustaceans and mollusks.  Local seafood markets are wonderful shopping grounds for the moray owner – be sure to try mussels, conch and various marine fishes.

Well-fed eels will coexist with smaller fish, but there is always the possibility of predation.  On the other hand, morays are not quick feeders, and indeed can be rather shy about this, so one must take care that they are getting enough food if they are housed with large, aggressive fishes.

Cautions

Moray eels are, like all their relatives, master escape artists.  If this occurs, be sure to move the animal back and forth in the aquarium once it is replaced, so that water is forced through the gills, and treat it with Stress Coat Marine to help replace the skin’s slime coat.

Even small morays are equipped with needle-sharp teeth, and they are not shy about using them in defense or if they mistake your finger for a tasty food item.  The resulting wound almost always becomes infected, and large animals can cause permanent damage.  These are definitely not fish for homes with children.

Longevity

Well cared for specimens can reach impressive ages in captivity.  A huge green moray I worked with at the Staten Island Zoo is still going strong at age 30+.

Snowflake Moray, Echidna nebulosa

Brilliantly patterned in black and white, this Indo-Pacific native averages 24 (rarely to 40) inches in length and makes an ideal first choice for one new to keeping moray eels.  Many individuals become quite tame, reaching out from their lairs to accept food offered on feeding tongs.

They are, like other members of their family, slow feeders, and so are best individually-fed if kept in a community aquarium.  Snowflakes readily accept all manner of frozen or fresh marine foods such as shrimp, clams and fish.  Like all morays, they will not thrive unless provided with a secure retreat.

Other Commonly-Available Moray Eels

The girdled moray (Echidna polyzona) hails from the Red Sea and Indo-Pacific and its small size (to 35 inches) suits it well as an aquarium subject.  It has a relatively small head ….food item size should be adjusted accordingly.

The attractively patterned reticulated or leopard moray (Gymnothorax tesselatus) also appears in the pet trade.  Pale reticulations on a dark background lend it a spectacular appearance, but it reaches 5 feet in length and is therefore suited only to large, very well-secured tanks.

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

You can learn more about moray eels at:

http://www.fishbase.com/Summary/FamilySummary.cfm?ID=56&CFID=17425107&CFTOKEN=61585937

Hello, Frank Indiviglio here. Please see Part I of this article for further information.

Feeding

The fan shrimp’s unique mode of feeding is very interesting to observe.  The first 2 appendages are lined with plume-like bristles which are waved about when food is detected.  Tiny organisms, organic detritus and algae are trapped in these and transferred to the mouth.  Fan shrimp will also pick food particles from the substrate, in more “typical shrimp” fashion, and I have several times observed them feeding on dead fish (at night).

If you keep fan shrimp with fish, it is important to introduce food at night, just before you turn out the lights…the shrimp will rarely get enough to eat otherwise.  I keep a few yo-yo loaches, Kuhli loaches and armored cats with mine, but beware of adding too many nocturnally-feeding fish.

Unlike many shrimps with specialized feeding adaptations, these accept nearly any pelleted or freeze dried food.  One of the few published reports on their feeding habits in the wild (please see below) established that fan shrimp are omnivorous, with algae forming a major part of the diet.  I therefore provide my shrimp with both plant and animal foods.  I use algae  and shrimp tablets as a basis of the diet, alternated with flake and freeze dried foods.  Liquid invertebrate food  may also be squirted into their hiding places.

African fan shrimp begin waving their feeding appendages about as soon as food is sensed.  I usually drop algae tabs or other foods right near them, after which they will move over it and begin waving away.  If you look closely, you’ll be able to see fine particles of food lodge in the brushes as the tablet dissolves.

My fan shrimp do not gravitate towards the filter outflow in order to trap food, as do the Singapore wood shrimp (Atyopsis moluccensis) which share their tank.  They will, however, filter fine food particles from whatever water currents pass by their lairs.  Some suggest keeping these shrimp in well-established tanks that house high populations of diatoms and other micro-organisms.  Certainly this is a good idea, but as we know little of their actual food intake needs, I would suggest that shrimp in these situations be fed as described above as well.

Social Grouping/Compatible Species

African fan shrimp do exceedingly well in same-species groups; I have also kept them with Singapore wood shrimp, Atyopsis moluccensis, Japanese marsh shrimp, Caridina japonica and cherry shrimp, Neocardina denticulate.  Small, peaceful community fish such as guppies, zebra danios, cherry barbs and so on are also fine, but please see the feeding cautions above.

Alternatively, you can house fan shrimp with fish that do not compete for food, i.e. live food specialists such as elephant-nosed morymids and butterfly fish (both of which are also native to West Africa, although not to the same habitat-types).

Small and large cichlids, carnivorous catfish and crayfish will attack fan shrimp.

Captive Longevity

Unpublished reports set captive longevity at just over 5 years.

Breeding

Anecdotal reports claim breeding success in heavily-planted outdoor ponds.  The young are said to be planktonic for a period of 2-3 weeks after hatching, which would certainly complicate matters in an aquarium.  I plan to look into this further and report back.

Miscellaneous

Fan shrimp are, as mentioned, very much oriented to a specific home cave, being more like crayfish than shrimp in this regard.  I imagine (but this has not been established) that such holds true in the wild as well.  I have observed them to become quite stressed if routed from their retreats.  In most cases, they wander about, often for days, before returning to the cave.

Be extremely careful when working around them, and avoid moving or re-arranging their caves.  I usually forego cleaning the glass directly in front of their caves, unless I happen to catch the shrimp “away from home” on rare foraging forays.  In those cases I’m always careful to return the rocks to their original position – a slight change in their shelter’s height or depth has seemingly caused my shrimp to seek “new accommodations”.

We have a great deal to learn about this and other freshwater invertebrates… please write in with your questions and comments. Thanks, Frank Indiviglio.

Very little has been published about this species in its natural habitat.  An interesting article concerning field research with fan shrimp in Nigeria is posted at:

http://www.wajae.org/papers/paper_vol13/Food_and_Feeding_Habits_of_Atya_gabonensis_from_Lower_River_Benue_in_Northern_Nigeria_full.pdf

Brandon here. One of my favorite types of fish is one that is often overlooked because it lacks the cute appearance that so many other saltwater fish brandish.  In fact, many people believe them to be one of the ugliest saltwater fish we import here at That Fish Place.  The orange toadfish and freshwater lionfish are just two of many different species that belong to an order of very odd looking fish.

All toadfish belong to the order Batrachoidiformes.  This order is home to around 80 different species of toadfish, most of which are saltwater and brackish species.  Toadfish are characterized by their scaleless bodies, extremely large mouths, powerful jaws, and drab color (with the exception of a few reef species).  They get their name from the croaking sound they produce from their swim bladder to communicate with one another and attract mates.  Caution should be taken when handling toadfish.  Many species have spines that can inflict painful wounds, and in certain species the spines are connected to venom glands.  Most species have very powerful jaws that, in a large individual, are even capable of breaking fingers!

In the aquarium, most toadfish are extremely hardy, although they are shy and tend to hide.  You can usually spot their faces poking out from under the rock work in your tank.  They can persist for extended periods of time without eating, but will gorge themselves when food is available.  Toadfish do well on a varied diet of frozen meats including shrimp, krill, squid, and fish.  Their food should be enriched with a vitamin supplement such as Vitachem to ensure that they are receiving proper nutrition.  Tank mates should be chosen carefully as toadfish will not hesitate to eat anything small enough to fit into their mouth, including each other.

Several classmates and I have been successful at breeding the Oyster Toadfish (Opsanus tau) in captivity.  In fact, they have been extremely easy to breed.  We placed seven individuals into a very large tank, fed them well, and the fish did the rest of the work.  A pair of toadfish would lay several dozen eggs on the roof and sides of a rock cave.  One of the parents would remain and stand guard.  The eggs were yellowish in color and about the size of a pea.  After about a week the eggs would hatch and the fry would stay bonded to the rock.  After a few more days the fry became free swimming and would go off in search of food.  They will not take frozen food, so live brine and ghost shrimp would be a better offering.

 While breeding the oyster toadfishes’ tropical cousins may not be as easy, they are still an interesting fish to keep in the home aquarium.  If you’re looking for a predator that is a little out of the ordinary, why not try a toadfish?

Bettas are one of the most popular fish for aquarists of all levels and many betta-keepers chose to combine their love of fish with their love of gardening to give their fish a natural planted environment. So what are the best plants to keep with bettas? The choices are endless! We’ll discuss a few options here as well as how to choose the best plants and how to set up your display.

Before we begin, it is important to note that the plant DOES NOT feed the betta! When the trend of keep a plant on top of a betta bowl first became popular, it was a common misconception that the betta would feed on the roots of the betta and wouldn’t need to be fed…that could hardly be farther from the truth. Bettas are carnivores, meaning they eat meaty food…NOT plants. A betta seen nibbling at a plant is more likely bored, starving, or picking off tiny animals on the surface of the plant. Even if you have live plants in the tank, you still need to feed your fish.

While bettas can be kept in tanks or large bowls (preferably at least 1 gallon at the absolute bare minimum) without a filter, the lack of filter means that the water would need to be changed more frequently. Those frequent changes can actually be harmful to some plants (especially rooted or bulb plants) if they are disturbed often.

On to choosing your plants…

Aquarium Plants:

This one may seem obvious but any live aquarium plants would be safe with a betta. The key is making sure that the water parameters and lighting on the tank are suitable for the plant. You can consult a Plant Requirements Chart like ours to make sure your lighting, hardness and other parameters are suitable. If your tank doesn’t have its own lighting, consider investing in a fixture if you would like higher-light plants or stick to low-light species. These plants are all generally tropical, meaning they need water at a consistent temperature, usually about 74-78 degrees…coincidentally, the same temperature your betta will thrive at as well. You may need a heater in the tank for both the fish and plants if your tank is in a cooler location or somewhere drafty that may cause the water temperature to be inconsistent. The plants (and fish) will also thrive better with a filter and gentle water movement.

Some popular and easy choices are fast-growing stalk plants like Anacharis, Hornwort, Myrio, Ludwigia and countless others. These plants are typically sold in bunches held together with a lead weight or rubberband. This should be removed when the plant is added to the tank and the stalks planted individually or left floating for some plants. Java Fern and Anubias plants are also popular low-light choices. These plants grow from a rhizome with roots coming from it that should be planted in the substrate. They would benefit from a plant substrate rather than decorative gravel and should be disturbed as little as possible once they are planted. Mosses are also good for betta tanks as well as floating plants like Duckweed or Azolla (just make sure they are allowed in your area as some areas prohibit some floating plants as invasive species). Many tissue-culture plants are also good for bettas since they are offered at a smaller size and are snail-free.

Partially-submerged plants

Many planted betta tanks can give you the opportunity to really think outside the box…literally. Some popular “betta plants” actually do much better with part of the plant extending above the water level. The two most common of these plants are the Brazilian Sword (also known as a “Peace Lily”) and “Lucky Bamboo”. For both of these, you can either plant the plant into the substrate so the top sticks out of the water or suspend the plant towards the top of the tank. We’ll cover how to do that later.

“House plants”

This is what we get questions about the most… “Can I keep my <insert plant here> in with my betta?” Unfortunately, there’s no easy answer but we can help you find the answer. The most important thing to consider here is the moisture level of the plant. Any plant that needs dry soil – cactus, succulents, Aloe, etc. – can’t be kept in a wet environment and would make a poor choice for your betta. At best, the plant wouldn’t survive. At worse, the dying plant would pollute the water and take the betta out with it. Instead, look for plants that can handle constantly wet soil. During the spring and summer, you can look for plants sold for outdoor ponds as “bog plants” or “marginal plants”. These plants live at the edges of ponds or swamps and are used to having their roots in water. Some popular species of these plants are the Peace Lilies and Bamboo we mentioned above as well as some ivy, Philodendrons, Spider Plants, Water Clover, Sensitive Plant, Violets and many more. Many plants sold as pond plants can grows very large or need full sunlight so just make sure you consider the needs of the plant carefully before adding it to your tank. As with any plants, you may need to prune or trim the plant as it grows so it doesn’t take over the tank. Also, some fertilizers or insecticides can be harmful to the betta so choose your plant carefully.

Suspending your plants

As we mentioned above, may popular set up with plants involve suspending the plant above the level of the tank. The most common of these is the hourglass-shaped betta vase with a “Peace Lily” (the Brazilian Sword from earlier) suspended at the neck of the vase but any plants that need their leafy bits above the water level can be kept this way. There are many ways to accomplish this and depend on the size, shape and setup of your tank. Some modern, high-end tanks even have a built-in section just for a live plant above the water but even if yours doesn’t you can create your own.

If you have a vase or tank with a narrow opening, you can set the bowl containing your plant right on top….just be sure to keep a fair amount of space between the water level and top of the vase, because bettas need an open space to breathe atmospheric air. If your tank has nothing to support the plant dish, you can suspend it using supports like bamboo rods, dowels, chopsticks or a similar material that is strong enough and will keep its strength with the moisture…avoid anything that will soften or metal that may rust. You can also use clips to hold the cup onto the side of the tank as long as they are strong enough to support the plant without stressing the tank. For a few ideas, check out these photos:

For the cup itself, you can use a clean plastic cup like the one pictured here in any size suitable for your tank and the plant, or a pot made of a plant-safe material like terracotta (as long as the support system can hold it). If the dish you choose doesn’t have a hole or holes for the roots to extend through, cut the center out while leaving a ledge around it so you can add some stones to support the plant. With the cup we used in our example, I would cut out the black area in the center. When adding some stones to keep the plant upright, it is best to use larger pebbles or gravel so it doesn’t fall through the hole into the tank below.

Hopefully, these ideas help you with some ideas for your own new betta display. As always, feel free to let us know if you have any questions or need help making your idea a reality!

For more information on bettas and their care, please read these helpful articles in our archives:

http://www.thatpetplace.com/pet/displayArticle.web?Filename=../Article_archive/Fish/Betta_Basics.html

http://blogs.thatpetplace.com/thatfishblog/2008/06/26/carnival-fish-part-2-the-betta/

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.

NATURAL HISTORY

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 HUSBANDRY

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.

Substrate

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.

Water

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: